pkgtools/pkglint: update to 20.1.16

Changes since 20.1.15:

When a package adds an additional version requirement for another
package, it must do so using BUILDLINK_API_DEPENDS instead of
BUILDLINK_ABI_DEPENDS.  Most packages already do this.

When a values is appended to an undefined variable using the += operator,
bmake does not add a space before, and pkglint caught up to do the same.
This change has no practical consequences though.

As always, a bit of refactoring.  The method names of MkAssignChecker
contained the redundant word "varassign".

18 files changed, 282 insertions, 155 deletions

diff --git a/pkgtools/pkglint/Makefile b/pkgtools/pkglint/Makefile
index 9966cc774a4..513a2a18e2c 100644
--- a/pkgtools/pkglint/Makefile
+++ b/pkgtools/pkglint/Makefile
@@ -1,6 +1,6 @@
-# $NetBSD: Makefile,v 1.654 2020/06/07 15:49:23 rillig Exp $
+# $NetBSD: Makefile,v 1.655 2020/06/12 19:14:45 rillig Exp $
 
-PKGNAME=	pkglint-20.1.15
+PKGNAME=	pkglint-20.1.16
 CATEGORIES=	pkgtools
 DISTNAME=	tools
 MASTER_SITES=	${MASTER_SITE_GITHUB:=golang/}
diff --git a/pkgtools/pkglint/files/buildlink3_test.go b/pkgtools/pkglint/files/buildlink3_test.go
index c5b374951aa..38989b159a6 100644
--- a/pkgtools/pkglint/files/buildlink3_test.go
+++ b/pkgtools/pkglint/files/buildlink3_test.go
@@ -305,6 +305,7 @@ func (s *Suite) Test_CheckLinesBuildlink3Mk__name_mismatch_abi_api(c *check.C) {
 	CheckLinesBuildlink3Mk(mklines)
 
 	t.CheckOutputLines(
+		"ERROR: buildlink3.mk:10: Packages must only require API versions, not ABI versions of dependencies.",
 		"WARN: buildlink3.mk:9: Package name mismatch between ABI \"hs-X12\" and API \"hs-X11\" (from line 8).",
 		"WARN: buildlink3.mk:10: Only buildlink variables for \"hs-X11\", not \"hs-X12\" may be set in this file.")
 }
diff --git a/pkgtools/pkglint/files/homepage_test.go b/pkgtools/pkglint/files/homepage_test.go
index ca7ae4f9efc..6566461e15f 100644
--- a/pkgtools/pkglint/files/homepage_test.go
+++ b/pkgtools/pkglint/files/homepage_test.go
@@ -64,8 +64,8 @@ func (s *Suite) Test_HomepageChecker_checkBasedOnMasterSites(c *check.C) {
 	vt.Output(
 		"WARN: filename.mk:11: HOMEPAGE should not be defined in terms of MASTER_SITEs.")
 
-	pkg.vars.v("MASTER_SITES").firstDef = nil
-	pkg.vars.v("MASTER_SITES").lastDef = nil
+	pkg.vars.create("MASTER_SITES").firstDef = nil
+	pkg.vars.create("MASTER_SITES").lastDef = nil
 	pkg.vars.Define("MASTER_SITES", t.NewMkLine(pkg.File("Makefile"), 5,
 		"MASTER_SITES=\thttps://cdn.NetBSD.org/pub/pkgsrc/distfiles/"))
 
@@ -76,8 +76,8 @@ func (s *Suite) Test_HomepageChecker_checkBasedOnMasterSites(c *check.C) {
 		"WARN: filename.mk:21: HOMEPAGE should not be defined in terms of MASTER_SITEs. " +
 			"Use https://cdn.NetBSD.org/pub/pkgsrc/distfiles/ directly.")
 
-	pkg.vars.v("MASTER_SITES").firstDef = nil
-	pkg.vars.v("MASTER_SITES").lastDef = nil
+	pkg.vars.create("MASTER_SITES").firstDef = nil
+	pkg.vars.create("MASTER_SITES").lastDef = nil
 	pkg.vars.Define("MASTER_SITES", t.NewMkLine(pkg.File("Makefile"), 5,
 		"MASTER_SITES=\t${MASTER_SITE_GITHUB}"))
 
@@ -89,8 +89,8 @@ func (s *Suite) Test_HomepageChecker_checkBasedOnMasterSites(c *check.C) {
 	vt.Output(
 		"WARN: filename.mk:31: HOMEPAGE should not be defined in terms of MASTER_SITEs.")
 
-	pkg.vars.v("MASTER_SITES").firstDef = nil
-	pkg.vars.v("MASTER_SITES").lastDef = nil
+	pkg.vars.create("MASTER_SITES").firstDef = nil
+	pkg.vars.create("MASTER_SITES").lastDef = nil
 	pkg.vars.Define("MASTER_SITES", t.NewMkLine(pkg.File("Makefile"), 5,
 		"MASTER_SITES=\t# none"))
 
diff --git a/pkgtools/pkglint/files/mkassignchecker.go b/pkgtools/pkglint/files/mkassignchecker.go
index 417c1b295c2..e2b074ce5f7 100644
--- a/pkgtools/pkglint/files/mkassignchecker.go
+++ b/pkgtools/pkglint/files/mkassignchecker.go
@@ -15,26 +15,27 @@ func NewMkAssignChecker(mkLine *MkLine, mkLines *MkLines) *MkAssignChecker {
 	return &MkAssignChecker{MkLine: mkLine, MkLines: mkLines}
 }
 
-func (ck *MkAssignChecker) checkVarassign() {
-	ck.checkVarassignLeft()
-	ck.checkVarassignOp()
-	ck.checkVarassignRight()
+func (ck *MkAssignChecker) check() {
+	ck.checkLeft()
+	ck.checkOp()
+	ck.checkRight()
 }
 
-// checkVarassignLeft checks everything to the left of the assignment operator.
-func (ck *MkAssignChecker) checkVarassignLeft() {
+// checkLeft checks everything to the left of the assignment operator.
+func (ck *MkAssignChecker) checkLeft() {
 	varname := ck.MkLine.Varname()
 	if hasPrefix(varname, "_") && !G.Infrastructure && G.Pkgsrc.vartypes.Canon(varname) == nil {
 		ck.MkLine.Warnf("Variable names starting with an underscore (%s) are reserved for internal pkgsrc use.", varname)
 	}
 
-	ck.checkVarassignLeftNotUsed()
-	ck.checkVarassignLeftDeprecated()
-	ck.checkVarassignLeftBsdPrefs()
-	if !ck.checkVarassignLeftUserSettable() {
-		ck.checkVarassignLeftPermissions()
+	ck.checkLeftNotUsed()
+	ck.checkLeftDeprecated()
+	ck.checkLeftBsdPrefs()
+	if !ck.checkLeftUserSettable() {
+		ck.checkLeftPermissions()
+		ck.checkLeftAbiDepends()
 	}
-	ck.checkVarassignLeftRationale()
+	ck.checkLeftRationale()
 
 	NewMkLineChecker(ck.MkLines, ck.MkLine).checkTextVarUse(
 		ck.MkLine.Varname(),
@@ -42,10 +43,10 @@ func (ck *MkAssignChecker) checkVarassignLeft() {
 		VucLoadTime)
 }
 
-// checkVarassignLeftNotUsed checks whether the left-hand side of a variable
+// checkLeftNotUsed checks whether the left-hand side of a variable
 // assignment is not used. If it is unused and also doesn't have a predefined
 // data type, it may be a spelling mistake.
-func (ck *MkAssignChecker) checkVarassignLeftNotUsed() {
+func (ck *MkAssignChecker) checkLeftNotUsed() {
 	varname := ck.MkLine.Varname()
 	varcanon := varnameCanon(varname)
 
@@ -90,7 +91,7 @@ func (ck *MkAssignChecker) checkVarassignLeftNotUsed() {
 		"see mk/subst.mk for an example of such a documentation comment.")
 }
 
-func (ck *MkAssignChecker) checkVarassignLeftDeprecated() {
+func (ck *MkAssignChecker) checkLeftDeprecated() {
 	varname := ck.MkLine.Varname()
 	if fix := G.Pkgsrc.Deprecated[varname]; fix != "" {
 		ck.MkLine.Warnf("Definition of %s is deprecated. %s", varname, fix)
@@ -99,7 +100,7 @@ func (ck *MkAssignChecker) checkVarassignLeftDeprecated() {
 	}
 }
 
-func (ck *MkAssignChecker) checkVarassignLeftBsdPrefs() {
+func (ck *MkAssignChecker) checkLeftBsdPrefs() {
 	mkline := ck.MkLine
 
 	switch mkline.Varcanon() {
@@ -147,10 +148,10 @@ func (ck *MkAssignChecker) checkVarassignLeftBsdPrefs() {
 		"bsd.prefs.mk file, which will take care of everything.")
 }
 
-// checkVarassignLeftUserSettable checks whether a package defines a
+// checkLeftUserSettable checks whether a package defines a
 // variable that is marked as user-settable since it is defined in
 // mk/defaults/mk.conf.
-func (ck *MkAssignChecker) checkVarassignLeftUserSettable() bool {
+func (ck *MkAssignChecker) checkLeftUserSettable() bool {
 	mkline := ck.MkLine
 	varname := mkline.Varname()
 
@@ -198,11 +199,11 @@ func (ck *MkAssignChecker) checkVarassignLeftUserSettable() bool {
 	return true
 }
 
-// checkVarassignLeftPermissions checks the permissions for the left-hand side
+// checkLeftPermissions checks the permissions for the left-hand side
 // of a variable assignment line.
 //
 // See checkPermissions.
-func (ck *MkAssignChecker) checkVarassignLeftPermissions() {
+func (ck *MkAssignChecker) checkLeftPermissions() {
 	if !G.WarnPerm {
 		return
 	}
@@ -273,7 +274,43 @@ func (ck *MkAssignChecker) checkVarassignLeftPermissions() {
 	}
 }
 
-func (ck *MkAssignChecker) checkVarassignLeftRationale() {
+func (ck *MkAssignChecker) checkLeftAbiDepends() {
+	mkline := ck.MkLine
+
+	varname := mkline.Varname()
+	if !hasPrefix(varname, "BUILDLINK_ABI_DEPENDS.") {
+		return
+	}
+
+	basename := mkline.Basename
+	if basename == "buildlink3.mk" {
+		varparam := varnameParam(varname)
+		bl3id := ""
+		for _, bl3line := range ck.MkLines.mklines {
+			if bl3line.IsVarassign() && bl3line.Varname() == "BUILDLINK_TREE" {
+				bl3id = bl3line.Value()
+				break
+			}
+		}
+		if varparam == bl3id {
+			return
+		}
+	}
+
+	fix := mkline.Autofix()
+	fix.Errorf("Packages must only require API versions, not ABI versions of dependencies.")
+	fix.Explain(
+		"When building a package from the sources,",
+		"the version of the installed package does not matter.",
+		"That version is specified by BUILDLINK_ABI_VERSION.",
+		"",
+		"The only version that matters is the API of the dependency,",
+		"which is selected by specifying BUILDLINK_API_DEPENDS.")
+	fix.Replace("BUILDLINK_ABI_DEPENDS", "BUILDLINK_API_DEPENDS")
+	fix.Apply()
+}
+
+func (ck *MkAssignChecker) checkLeftRationale() {
 	if !G.WarnExtra {
 		return
 	}
@@ -305,11 +342,11 @@ func (ck *MkAssignChecker) checkVarassignLeftRationale() {
 		"* has it been reported upstream?")
 }
 
-func (ck *MkAssignChecker) checkVarassignOp() {
-	ck.checkVarassignOpShell()
+func (ck *MkAssignChecker) checkOp() {
+	ck.checkOpShell()
 }
 
-func (ck *MkAssignChecker) checkVarassignOpShell() {
+func (ck *MkAssignChecker) checkOpShell() {
 	mkline := ck.MkLine
 
 	switch {
@@ -356,8 +393,8 @@ func (ck *MkAssignChecker) checkVarassignOpShell() {
 		"or .for directive.")
 }
 
-// checkVarassignLeft checks everything to the right of the assignment operator.
-func (ck *MkAssignChecker) checkVarassignRight() {
+// checkLeft checks everything to the right of the assignment operator.
+func (ck *MkAssignChecker) checkRight() {
 	mkline := ck.MkLine
 	varname := mkline.Varname()
 	op := mkline.Op()
@@ -372,12 +409,12 @@ func (ck *MkAssignChecker) checkVarassignRight() {
 	mkLineChecker.checkText(value)
 	mkLineChecker.checkVartype(varname, op, value, comment)
 
-	ck.checkVarassignMisc()
+	ck.checkMisc()
 
-	ck.checkVarassignRightVaruse()
+	ck.checkRightVaruse()
 }
 
-func (ck *MkAssignChecker) checkVarassignRightCategory() {
+func (ck *MkAssignChecker) checkRightCategory() {
 	mkline := ck.MkLine
 	if mkline.Op() != opAssign && mkline.Op() != opAssignDefault {
 		return
@@ -403,7 +440,7 @@ func (ck *MkAssignChecker) checkVarassignRightCategory() {
 	fix.Apply()
 }
 
-func (ck *MkAssignChecker) checkVarassignMisc() {
+func (ck *MkAssignChecker) checkMisc() {
 	mkline := ck.MkLine
 	varname := mkline.Varname()
 	value := mkline.Value()
@@ -413,7 +450,7 @@ func (ck *MkAssignChecker) checkVarassignMisc() {
 	}
 
 	if varname == "PYTHON_VERSIONS_ACCEPTED" {
-		ck.checkVarassignDecreasingVersions()
+		ck.checkDecreasingVersions()
 	}
 
 	if mkline.Comment() == " defined" && !hasSuffix(varname, "_MK") && !hasSuffix(varname, "_COMMON") {
@@ -444,14 +481,16 @@ func (ck *MkAssignChecker) checkVarassignMisc() {
 
 	if varname == "PKG_SKIP_REASON" && ck.MkLines.indentation.DependsOn("OPSYS") {
 		// TODO: Provide autofix for simple cases, like ".if ${OPSYS} == SunOS".
+		// This needs support for high-level refactoring tools though.
+		// As of June 2020, refactoring is limited to text replacements in single lines.
 		mkline.Notef("Consider setting NOT_FOR_PLATFORM instead of " +
 			"PKG_SKIP_REASON depending on ${OPSYS}.")
 	}
 
-	ck.checkVarassignMiscRedundantInstallationDirs()
+	ck.checkMiscRedundantInstallationDirs()
 }
 
-func (ck *MkAssignChecker) checkVarassignDecreasingVersions() {
+func (ck *MkAssignChecker) checkDecreasingVersions() {
 	mkline := ck.MkLine
 	strVersions := mkline.Fields()
 	intVersions := make([]int, len(strVersions))
@@ -475,7 +514,7 @@ func (ck *MkAssignChecker) checkVarassignDecreasingVersions() {
 	}
 }
 
-func (ck *MkAssignChecker) checkVarassignMiscRedundantInstallationDirs() {
+func (ck *MkAssignChecker) checkMiscRedundantInstallationDirs() {
 	mkline := ck.MkLine
 	varname := mkline.Varname()
 	pkg := ck.MkLines.pkg
@@ -502,10 +541,10 @@ func (ck *MkAssignChecker) checkVarassignMiscRedundantInstallationDirs() {
 	}
 }
 
-// checkVarassignRightVaruse checks that in a variable assignment,
+// checkRightVaruse checks that in a variable assignment,
 // each variable used on the right-hand side of the assignment operator
 // has the correct data type and quoting.
-func (ck *MkAssignChecker) checkVarassignRightVaruse() {
+func (ck *MkAssignChecker) checkRightVaruse() {
 	if trace.Tracing {
 		defer trace.Call0()()
 	}
@@ -524,16 +563,16 @@ func (ck *MkAssignChecker) checkVarassignRightVaruse() {
 	}
 
 	if vartype != nil && vartype.IsShell() {
-		ck.checkVarassignVaruseShell(vartype, time)
+		ck.checkVaruseShell(vartype, time)
 	} else {
 		mkLineChecker := NewMkLineChecker(ck.MkLines, ck.MkLine)
 		mkLineChecker.checkTextVarUse(ck.MkLine.Value(), vartype, time)
 	}
 }
 
-// checkVarassignVaruseShell is very similar to checkVarassignRightVaruse, they just differ
+// checkVaruseShell is very similar to checkRightVaruse, they just differ
 // in the way they determine isWordPart.
-func (ck *MkAssignChecker) checkVarassignVaruseShell(vartype *Vartype, time VucTime) {
+func (ck *MkAssignChecker) checkVaruseShell(vartype *Vartype, time VucTime) {
 	if trace.Tracing {
 		defer trace.Call(vartype, time)()
 	}
diff --git a/pkgtools/pkglint/files/mkassignchecker_test.go b/pkgtools/pkglint/files/mkassignchecker_test.go
index 7164f4ae625..3bf22bb2902 100644
--- a/pkgtools/pkglint/files/mkassignchecker_test.go
+++ b/pkgtools/pkglint/files/mkassignchecker_test.go
@@ -10,14 +10,14 @@ func (s *Suite) Test_NewMkAssignChecker(c *check.C) {
 
 	ck := NewMkAssignChecker(mklines.mklines[0], mklines)
 
-	ck.checkVarassign()
+	ck.check()
 
 	t.CheckOutputLines(
 		"WARN: filename.mk:1: VAR is defined but not used.",
 		"WARN: filename.mk:1: OTHER is used but not defined.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassign(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_check(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -34,7 +34,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassign(c *check.C) {
 
 // Pkglint once interpreted all lists as consisting of shell tokens,
 // splitting this URL at the ampersand.
-func (s *Suite) Test_MkAssignChecker_checkVarassign__URL_with_shell_special_characters(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_check__URL_with_shell_special_characters(c *check.C) {
 	t := s.Init(c)
 
 	pkg := NewPackage(t.File("graphics/gimp-fix-ca"))
@@ -48,7 +48,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassign__URL_with_shell_special_char
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassign__list(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_check__list(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpMasterSite("MASTER_SITE_GITHUB", "https://github.com/")
@@ -82,7 +82,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassign__list(c *check.C) {
 		"")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeft(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeft(c *check.C) {
 	t := s.Init(c)
 
 	mklines := t.NewMkLines("module.mk",
@@ -100,7 +100,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeft(c *check.C) {
 
 // Files from the pkgsrc infrastructure may define and use variables
 // whose name starts with an underscore.
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeft__infrastructure(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeft__infrastructure(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -116,7 +116,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeft__infrastructure(c *check
 		"WARN: ~/mk/infra.mk:2: _VARNAME is defined but not used.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeft__documented_underscore(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeft__documented_underscore(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -130,7 +130,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeft__documented_underscore(c
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__procedure_call(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftNotUsed__procedure_call(c *check.C) {
 	t := s.Init(c)
 
 	t.CreateFileLines("mk/pkg-build-options.mk")
@@ -156,7 +156,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__procedure_call(c
 		"WARN: ~/category/package/filename.mk:6: VAR is defined but not used.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__procedure_call_no_tracing(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftNotUsed__procedure_call_no_tracing(c *check.C) {
 	t := s.Init(c)
 
 	t.DisableTracing() // Just for code coverage
@@ -172,7 +172,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__procedure_call_n
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__infra(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftNotUsed__infra(c *check.C) {
 	t := s.Init(c)
 
 	t.CreateFileLines("mk/infra.mk",
@@ -200,7 +200,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftNotUsed__infra(c *check.C
 		"WARN: ~/category/package/Makefile:22: UNDOCUMENTED is used but not defined.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftDeprecated(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftDeprecated(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -211,7 +211,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftDeprecated(c *check.C) {
 			varname+"=\t# none")
 		ck := NewMkAssignChecker(mklines.mklines[0], mklines)
 
-		ck.checkVarassignLeftDeprecated()
+		ck.checkLeftDeprecated()
 
 		t.CheckOutput(diagnostics)
 	}
@@ -224,7 +224,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftDeprecated(c *check.C) {
 		nil...)
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftBsdPrefs(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpCommandLine("-Wall", "--only", "bsd.prefs.mk")
@@ -257,7 +257,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs(c *check.C) {
 // Up to 2019-12-03, pkglint didn't issue a warning if a default assignment
 // to a package-settable variable appeared before one to a user-settable
 // variable. This was a mistake.
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs__first_time(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftBsdPrefs__first_time(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -276,7 +276,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs__first_time(c *c
 			"be given a default value by any package.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs__vartype_nil(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftBsdPrefs__vartype_nil(c *check.C) {
 	t := s.Init(c)
 
 	mklines := t.NewMkLines("builtin.mk",
@@ -290,7 +290,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftBsdPrefs__vartype_nil(c *
 		"WARN: builtin.mk:2: Please include \"../../mk/bsd.prefs.mk\" before using \"?=\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftUserSettable(c *check.C) {
 	t := s.Init(c)
 
 	// TODO: Allow CreateFileLines before SetUpPackage, since it matches
@@ -335,7 +335,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable(c *check.C)
 			"which differs from the default value \"default\" from mk/defaults/mk.conf.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__before_prefs(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftUserSettable__before_prefs(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpCommandLine("-Wall", "--explain")
@@ -358,7 +358,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__before_pref
 		"")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__after_prefs(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftUserSettable__after_prefs(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpCommandLine("-Wall", "--explain")
@@ -377,7 +377,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__after_prefs
 		"NOTE: Makefile:21: Redundant definition for AFTER from mk/defaults/mk.conf.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__vartype_nil(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftUserSettable__vartype_nil(c *check.C) {
 	t := s.Init(c)
 
 	t.CreateFileLines("category/package/allVars.mk",
@@ -405,7 +405,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftUserSettable__vartype_nil
 		"WARN: Makefile:20: USER_SETTABLE is defined but not used.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__hacks_mk(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftPermissions__hacks_mk(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -422,7 +422,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__hacks_mk(c *
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftPermissions(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -466,7 +466,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions(c *check.C) {
 			"but not options.mk.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__no_tracing(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftPermissions__no_tracing(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -483,7 +483,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__no_tracing(c
 // languages like Perl or Python that suggest certain licenses.
 //
 // The default license is typically set in a Makefile.common or module.mk.
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__license_default(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftPermissions__license_default(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -502,7 +502,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__license_defa
 }
 
 // Don't check the permissions for infrastructure files since they have their own rules.
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__infrastructure(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkLeftPermissions__infrastructure(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -517,7 +517,26 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftPermissions__infrastructu
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignLeftRationale(c *check.C) {
+// Seen in x11/gtkmm3 before 2020-06-07.
+func (s *Suite) Test_MkAssignChecker_checkLeftAbiDepends(c *check.C) {
+	t := s.Init(c)
+
+	t.SetUpPackage("category/package",
+		"BUILDLINK_ABI_DEPENDS.lib+=\tlib>=1.0")
+	t.Chdir("category/package")
+	t.FinishSetUp()
+
+	G.Check(".")
+
+	// It may be a good idea to not only check the buildlink identifier
+	// for ${BUILDLINK_PREFIX.*} but also for appending to
+	// BUILDLINK_API_DEPENDS and BUILDLINK_ABI_DEPENDS.
+	t.CheckOutputLines(
+		"ERROR: Makefile:20: Packages must only require API versions, " +
+			"not ABI versions of dependencies.")
+}
+
+func (s *Suite) Test_MkAssignChecker_checkLeftRationale(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -608,7 +627,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignLeftRationale(c *check.C) {
 		nil...)
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignOp(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkOp(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpTool("uname", "UNAME", AfterPrefsMk)
@@ -630,7 +649,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignOp(c *check.C) {
 			"bsd.prefs.mk has to be included before.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignOpShell(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkOpShell(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpTool("uname", "UNAME", AfterPrefsMk)
@@ -706,7 +725,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignOpShell(c *check.C) {
 		"WARN: ~/category/package/standalone.mk:15: Please use \"${ECHO}\" instead of \"echo\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRight(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRight(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -715,7 +734,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRight(c *check.C) {
 
 	mklines.ForEach(func(mkline *MkLine) {
 		ck := NewMkAssignChecker(mkline, mklines)
-		ck.checkVarassignRight()
+		ck.checkRight()
 	})
 
 	// No warning about the UNKNOWN variable on the left-hand side,
@@ -726,7 +745,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRight(c *check.C) {
 		"WARN: filename.mk:1: Unknown shell command \"make\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__none(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__none(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -738,7 +757,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__none(c *check.
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__indirect(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__indirect(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -756,7 +775,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__indirect(c *ch
 			"Invalid category \"${PKGPATH:C,/.*,,}\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__wrong(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__wrong(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -769,7 +788,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__wrong(c *check
 		"WARN: ~/obscure/package/Makefile:5: The primary category should be \"obscure\", not \"perl5\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__wrong_in_package_directory(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__wrong_in_package_directory(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -785,7 +804,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__wrong_in_packa
 
 // Allow any primary category in "packages" from regress/*.
 // These packages won't be installed in a regular pkgsrc installation anyway.
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__regress(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__regress(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("regress/regress-package",
@@ -802,7 +821,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__regress(c *che
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__append(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__append(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -817,7 +836,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__append(c *chec
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__default(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__default(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -831,7 +850,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__default(c *che
 		"WARN: ~/obscure/package/Makefile:5: The primary category should be \"obscure\", not \"perl5\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__autofix(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__autofix(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpCommandLine("-Wall", "--autofix")
@@ -846,7 +865,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__autofix(c *che
 			"Replacing \"perl5 obscure\" with \"obscure perl5\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__third(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__third(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -865,7 +884,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__third(c *check
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__other_file(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightCategory__other_file(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("obscure/package",
@@ -885,7 +904,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightCategory__other_file(c *
 			"The primary category should be \"obscure\", not \"perl5\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignMisc(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkMisc(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -946,7 +965,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignMisc(c *check.C) {
 			"as it includes the PKGREVISION. Please use PKGVERSION_NOREV instead.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignMisc__multiple_inclusion_guards(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkMisc__multiple_inclusion_guards(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPkgsrc()
@@ -977,7 +996,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignMisc__multiple_inclusion_guar
 			"instead of \"# defined\".")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignDecreasingVersions(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkDecreasingVersions(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -996,7 +1015,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignDecreasingVersions(c *check.C
 	mklines.Check()
 
 	// Half of these warnings are from VartypeCheck.Enum,
-	// the other half are from checkVarassignDecreasingVersions.
+	// the other half are from checkDecreasingVersions.
 	// Strictly speaking some of them are redundant, but that's ok.
 	// They all need to be fixed in the end.
 	t.CheckOutputLines(
@@ -1016,7 +1035,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignDecreasingVersions(c *check.C
 			"Use one of { 27 36 37 38 } instead.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs__AUTO_MKDIRS_yes(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkMiscRedundantInstallationDirs__AUTO_MKDIRS_yes(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("category/package",
@@ -1037,7 +1056,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs
 			"The directory \"man\" is redundant in INSTALLATION_DIRS.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs__AUTO_MKDIRS_no(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkMiscRedundantInstallationDirs__AUTO_MKDIRS_no(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("category/package",
@@ -1054,7 +1073,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs
 	t.CheckOutputEmpty()
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs__absolute(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkMiscRedundantInstallationDirs__absolute(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpPackage("category/package",
@@ -1074,7 +1093,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignMiscRedundantInstallationDirs
 			"must be relative to ${PREFIX}.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignRightVaruse(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkRightVaruse(c *check.C) {
 	t := s.Init(c)
 
 	t.SetUpVartypes()
@@ -1090,7 +1109,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignRightVaruse(c *check.C) {
 		"NOTE: module.mk:2: The :Q modifier isn't necessary for ${LOCALBASE} here.")
 }
 
-func (s *Suite) Test_MkAssignChecker_checkVarassignVaruseShell(c *check.C) {
+func (s *Suite) Test_MkAssignChecker_checkVaruseShell(c *check.C) {
 	t := s.Init(c)
 
 	mklines := t.NewMkLines("filename.mk",
@@ -1098,7 +1117,7 @@ func (s *Suite) Test_MkAssignChecker_checkVarassignVaruseShell(c *check.C) {
 
 	mklines.ForEach(func(mkline *MkLine) {
 		ck := NewMkAssignChecker(mkline, mklines)
-		ck.checkVarassignRight()
+		ck.checkRight()
 	})
 
 	t.CheckOutputLines(
diff --git a/pkgtools/pkglint/files/mkline_test.go b/pkgtools/pkglint/files/mkline_test.go
index a4510c4a4d2..2e77fae2dc0 100644
--- a/pkgtools/pkglint/files/mkline_test.go
+++ b/pkgtools/pkglint/files/mkline_test.go
@@ -634,7 +634,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__append_URL_to_list_of_URLs(c *
 
 	t.CheckEquals(nq, no)
 
-	NewMkAssignChecker(mkline, mklines).checkVarassign()
+	NewMkAssignChecker(mkline, mklines).check()
 
 	t.CheckOutputEmpty() // Up to version 5.3.6, pkglint warned about a missing :Q here, which was wrong.
 }
@@ -648,7 +648,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__append_list_to_list(c *check.C
 		MkCvsID,
 		"MASTER_SITES=\t${MASTER_SITE_SOURCEFORGE:=squirrel-sql/}")
 
-	NewMkAssignChecker(mklines.mklines[1], mklines).checkVarassign()
+	NewMkAssignChecker(mklines.mklines[1], mklines).check()
 
 	// Assigning lists to lists is ok.
 	t.CheckOutputEmpty()
@@ -669,7 +669,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__eval_shell(c *check.C) {
 
 	mklines.ForEach(func(mkline *MkLine) {
 		if mkline.IsVarassign() {
-			NewMkAssignChecker(mkline, mklines).checkVarassign()
+			NewMkAssignChecker(mkline, mklines).check()
 		}
 	})
 
@@ -685,7 +685,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__command_in_single_quotes(c *ch
 		MkCvsID,
 		"SUBST_SED.hpath=\t-e 's|^\\(INSTALL[\t:]*=\\).*|\\1${INSTALL}|'")
 
-	NewMkAssignChecker(mklines.mklines[1], mklines).checkVarassign()
+	NewMkAssignChecker(mklines.mklines[1], mklines).check()
 
 	t.CheckOutputLines(
 		"WARN: Makefile:2: Please use ${INSTALL:Q} instead of ${INSTALL} " +
@@ -933,7 +933,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__PKGNAME_and_URL_list_in_URL_li
 		MkCvsID,
 		"MASTER_SITES=\tftp://ftp.gtk.org/${PKGNAME}/ ${MASTER_SITE_GNOME:=subdir/}")
 
-	NewMkAssignChecker(mklines.mklines[1], mklines).checkVarassignRightVaruse()
+	NewMkAssignChecker(mklines.mklines[1], mklines).checkRightVaruse()
 
 	t.CheckOutputEmpty() // Don't warn about missing :Q modifiers.
 }
@@ -948,7 +948,7 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__tool_in_CONFIGURE_ENV(c *check
 		"",
 		"CONFIGURE_ENV+=\tSYS_TAR_COMMAND_PATH=${TOOLS_TAR:Q}")
 
-	NewMkAssignChecker(mklines.mklines[2], mklines).checkVarassignRightVaruse()
+	NewMkAssignChecker(mklines.mklines[2], mklines).checkRightVaruse()
 
 	// The TOOLS_* variables only contain the path to the tool,
 	// without any additional arguments that might be necessary
@@ -969,8 +969,8 @@ func (s *Suite) Test_MkLine_VariableNeedsQuoting__backticks(c *check.C) {
 		"COMPILE_CMD=\tcc `${CAT} ${WRKDIR}/compileflags`",
 		"COMMENT_CMD=\techo `echo ${COMMENT}`")
 
-	NewMkAssignChecker(mklines.mklines[2], mklines).checkVarassignRightVaruse()
-	NewMkAssignChecker(mklines.mklines[3], mklines).checkVarassignRightVaruse()
+	NewMkAssignChecker(mklines.mklines[2], mklines).checkRightVaruse()
+	NewMkAssignChecker(mklines.mklines[3], mklines).checkRightVaruse()
 
 	// Both CAT and WRKDIR are safe from quoting, therefore no warnings.
 	// But COMMENT may contain arbitrary characters and therefore must
diff --git a/pkgtools/pkglint/files/mklinechecker.go b/pkgtools/pkglint/files/mklinechecker.go
index 5c2fbd24699..082a019549f 100644
--- a/pkgtools/pkglint/files/mklinechecker.go
+++ b/pkgtools/pkglint/files/mklinechecker.go
@@ -24,7 +24,7 @@ func (ck MkLineChecker) Check() {
 
 	switch {
 	case mkline.IsVarassign():
-		NewMkAssignChecker(mkline, ck.MkLines).checkVarassign()
+		NewMkAssignChecker(mkline, ck.MkLines).check()
 
 	case mkline.IsShellCommand():
 		ck.checkShellCommand()
@@ -171,7 +171,7 @@ func (ck MkLineChecker) checkVartype(varname string, op MkOperator, value, comme
 		}
 		if vartype.basicType == BtCategory {
 			mkAssignChecker := NewMkAssignChecker(mkline, ck.MkLines)
-			mkAssignChecker.checkVarassignRightCategory()
+			mkAssignChecker.checkRightCategory()
 		}
 		for _, word := range words {
 			ck.CheckVartypeBasic(varname, vartype.basicType, op, word, comment, vartype.IsGuessed())
diff --git a/pkgtools/pkglint/files/mklines_test.go b/pkgtools/pkglint/files/mklines_test.go
index cfc0d4040e1..1e00933262f 100644
--- a/pkgtools/pkglint/files/mklines_test.go
+++ b/pkgtools/pkglint/files/mklines_test.go
@@ -222,6 +222,28 @@ func (s *Suite) Test_MkLines_Check__PKG_SKIP_REASON_depending_on_OPSYS(c *check.
 		"NOTE: Makefile:7: Consider setting NOT_FOR_PLATFORM instead of PKG_SKIP_REASON depending on ${OPSYS}.")
 }
 
+func (s *Suite) Test_MkLines_Check__PKG_SKIP_REASON_depending_on_OPSYS_and_others(c *check.C) {
+	t := s.Init(c)
+
+	t.SetUpPkgsrc()
+	t.Chdir("category/package")
+	t.FinishSetUp()
+	mklines := t.NewMkLines("Makefile",
+		MkCvsID,
+		"",
+		".include \"../../mk/bsd.prefs.mk\"",
+		"",
+		"PKG_SKIP_REASON+=\t\"Fails everywhere\"",
+		".if ${OPSYS} == \"Cygwin\" && ${MACHINE_ARCH} == i386",
+		"PKG_SKIP_REASON+=\t\"Fails on Cygwin i386\"",
+		".endif")
+
+	mklines.Check()
+
+	t.CheckOutputLines(
+		"NOTE: Makefile:7: Consider setting NOT_FOR_PLATFORM instead of PKG_SKIP_REASON depending on ${OPSYS}.")
+}
+
 func (s *Suite) Test_MkLines_Check__use_list_variable_as_part_of_word(c *check.C) {
 	t := s.Init(c)
 
@@ -495,7 +517,7 @@ func (s *Suite) Test_MkLines_collectUsedVariables__simple(c *check.C) {
 	mklines.collectUsedVariables()
 
 	t.Check(mklines.allVars.vs, check.HasLen, 1)
-	t.CheckEquals(mklines.allVars.v("VAR").used, mkline)
+	t.CheckEquals(mklines.allVars.create("VAR").used, mkline)
 	t.CheckEquals(mklines.allVars.FirstUse("VAR"), mkline)
 }
 
diff --git a/pkgtools/pkglint/files/mkvarusechecker.go b/pkgtools/pkglint/files/mkvarusechecker.go
index 30c244b4b0f..4a3c79aedad 100644
--- a/pkgtools/pkglint/files/mkvarusechecker.go
+++ b/pkgtools/pkglint/files/mkvarusechecker.go
@@ -194,7 +194,7 @@ func (ck *MkVarUseChecker) checkVarnameBuildlink(varname string) {
 // be it in a variable assignment, in a shell command, a conditional, or
 // somewhere else.
 //
-// See checkVarassignLeftPermissions.
+// See MkAssignChecker.checkLeftPermissions.
 func (ck *MkVarUseChecker) checkPermissions(vuc *VarUseContext) {
 	if !G.WarnPerm {
 		return
diff --git a/pkgtools/pkglint/files/mkvarusechecker_test.go b/pkgtools/pkglint/files/mkvarusechecker_test.go
index fcd2dbbd83f..b56a2bd2f89 100644
--- a/pkgtools/pkglint/files/mkvarusechecker_test.go
+++ b/pkgtools/pkglint/files/mkvarusechecker_test.go
@@ -1083,7 +1083,7 @@ func (s *Suite) Test_MkVarUseChecker_checkAssignable(c *check.C) {
 
 	mklines.ForEach(func(mkline *MkLine) {
 		ck := NewMkAssignChecker(mkline, mklines)
-		ck.checkVarassignRight()
+		ck.checkRight()
 	})
 
 	t.CheckOutputLines(
@@ -1117,7 +1117,7 @@ func (s *Suite) Test_MkVarUseChecker_checkAssignable__shell_command_to_pathname(
 
 	mklines.ForEach(func(mkline *MkLine) {
 		ck := NewMkAssignChecker(mkline, mklines)
-		ck.checkVarassignRight()
+		ck.checkRight()
 	})
 
 	t.CheckOutputLines(
diff --git a/pkgtools/pkglint/files/package.go b/pkgtools/pkglint/files/package.go
index aa2e32fe68f..ddc6a463a51 100644
--- a/pkgtools/pkglint/files/package.go
+++ b/pkgtools/pkglint/files/package.go
@@ -118,7 +118,7 @@ func NewPackage(dir CurrPath) *Package {
 		conditionalIncludes:   make(map[PackagePath]*MkLine),
 		unconditionalIncludes: make(map[PackagePath]*MkLine),
 	}
-	pkg.vars.DefineAll(G.Pkgsrc.UserDefinedVars)
+	pkg.vars.DefineAll(&G.Pkgsrc.UserDefinedVars)
 
 	pkg.vars.Fallback("PKGDIR", ".")
 	pkg.vars.Fallback("DISTINFO_FILE", "${PKGDIR}/distinfo")
@@ -157,7 +157,7 @@ func (pkg *Package) load() ([]CurrPath, *MkLines, *MkLines) {
 		files = append(files, pkg.File(pkg.Pkgdir).ReadPaths()...)
 	}
 	files = append(files, pkg.File(pkg.Patchdir).ReadPaths()...)
-	if pkg.DistinfoFile != NewPackagePathString(pkg.vars.v("DISTINFO_FILE").fallback) {
+	if pkg.DistinfoFile != NewPackagePathString(pkg.vars.create("DISTINFO_FILE").fallback) {
 		files = append(files, pkg.File(pkg.DistinfoFile))
 	}
 
diff --git a/pkgtools/pkglint/files/redundantscope_test.go b/pkgtools/pkglint/files/redundantscope_test.go
index a919fbdf667..e7b7e3c50bd 100644
--- a/pkgtools/pkglint/files/redundantscope_test.go
+++ b/pkgtools/pkglint/files/redundantscope_test.go
@@ -428,6 +428,7 @@ func (s *Suite) Test_RedundantScope__before_including_same_value(c *check.C) {
 		"NOTE: including.mk:2: Default assignment of VAR.def.asg has no effect because of included.mk:2.",
 		"NOTE: including.mk:4: Definition of VAR.asg.def is redundant because of included.mk:4.",
 		"NOTE: including.mk:5: Definition of VAR.asg.asg is redundant because of included.mk:5.",
+		"NOTE: including.mk:7: Definition of VAR.app.def is redundant because of included.mk:7.",
 		"WARN: including.mk:8: Variable VAR.app.asg is overwritten in included.mk:8.")
 }
 
diff --git a/pkgtools/pkglint/files/shell_test.go b/pkgtools/pkglint/files/shell_test.go
index e4d25b9785f..b6ff89b4aba 100644
--- a/pkgtools/pkglint/files/shell_test.go
+++ b/pkgtools/pkglint/files/shell_test.go
@@ -1393,7 +1393,7 @@ func (s *Suite) Test_ShellLineChecker_CheckWord(c *check.C) {
 	t.SetUpVartypes()
 
 	test := func(shellWord string, checkQuoting bool, diagnostics ...string) {
-		// See checkVaruseUndefined and checkVarassignLeftNotUsed.
+		// See MkVarUseChecker.checkUndefined and MkAssignChecker.checkLeftNotUsed.
 		ck := t.NewShellLineChecker("\t echo " + shellWord)
 		ck.CheckWord(shellWord, checkQuoting, RunTime)
 		t.CheckOutput(diagnostics)
diff --git a/pkgtools/pkglint/files/util.go b/pkgtools/pkglint/files/util.go
index 823df9cbe02..ee44ceb9bfc 100644
--- a/pkgtools/pkglint/files/util.go
+++ b/pkgtools/pkglint/files/util.go
@@ -617,7 +617,8 @@ func (o *Once) check(key uint64) bool {
 //
 // See also RedundantScope.
 type Scope struct {
-	vs map[string]*scopeVar
+	vs    map[string]*scopeVar
+	names []string
 }
 
 type scopeVar struct {
@@ -631,15 +632,30 @@ type scopeVar struct {
 }
 
 func NewScope() Scope {
-	return Scope{make(map[string]*scopeVar)}
+	return Scope{make(map[string]*scopeVar), nil}
 }
 
-func (s *Scope) v(varname string) *scopeVar {
-	if v, found := s.vs[varname]; found {
+func (s *Scope) varnames() []string {
+	if len(s.names) == 0 && len(s.vs) > 0 {
+		varnames := make([]string, len(s.vs))
+		i := 0
+		for varname := range s.vs {
+			varnames[i] = varname
+			i++
+		}
+		sort.Strings(varnames)
+		s.names = varnames
+	}
+	return s.names
+}
+
+func (s *Scope) create(varname string) *scopeVar {
+	if v := s.vs[varname]; v != nil {
 		return v
 	}
 	var sv scopeVar
 	s.vs[varname] = &sv
+	s.names = nil
 	return &sv
 }
 
@@ -653,7 +669,7 @@ func (s *Scope) Define(varname string, mkline *MkLine) {
 }
 
 func (s *Scope) def(name string, mkline *MkLine) {
-	v := s.v(name)
+	v := s.create(name)
 	if v.firstDef == nil {
 		v.firstDef = mkline
 		if trace.Tracing {
@@ -694,13 +710,13 @@ func (s *Scope) def(name string, mkline *MkLine) {
 }
 
 func (s *Scope) Fallback(varname string, value string) {
-	s.v(varname).fallback = value
+	s.create(varname).fallback = value
 }
 
 // Use marks the variable and its canonicalized form as used.
 func (s *Scope) Use(varname string, line *MkLine, time VucTime) {
 	use := func(name string) {
-		v := s.v(name)
+		v := s.create(name)
 		if v.used == nil {
 			v.used = line
 			if trace.Tracing {
@@ -721,7 +737,10 @@ func (s *Scope) Use(varname string, line *MkLine, time VucTime) {
 //  - mentioned in a commented variable assignment,
 //  - mentioned in a documentation comment.
 func (s *Scope) Mentioned(varname string) *MkLine {
-	return s.v(varname).firstDef
+	if v := s.vs[varname]; v != nil {
+		return v.firstDef
+	}
+	return nil
 }
 
 // IsDefined tests whether the variable is defined.
@@ -730,7 +749,7 @@ func (s *Scope) Mentioned(varname string) *MkLine {
 // Even if IsDefined returns true, FirstDefinition doesn't necessarily return true
 // since the latter ignores the default definitions from vardefs.go, keyword dummyVardefMkline.
 func (s *Scope) IsDefined(varname string) bool {
-	mkline := s.v(varname).firstDef
+	mkline := s.Mentioned(varname)
 	return mkline != nil && mkline.IsVarassign()
 }
 
@@ -756,21 +775,19 @@ func (s *Scope) IsDefinedSimilar(varname string) bool {
 // IsUsed tests whether the variable is used.
 // It does NOT test the canonicalized variable name.
 func (s *Scope) IsUsed(varname string) bool {
-	return s.v(varname).used != nil
+	return s.FirstUse(varname) != nil
 }
 
 // IsUsedSimilar tests whether the variable or its canonicalized form is used.
 func (s *Scope) IsUsedSimilar(varname string) bool {
-	if s.v(varname).used != nil {
-		return true
-	}
-	return s.v(varnameCanon(varname)).used != nil
+	return s.FirstUse(varname) != nil || s.FirstUse(varnameCanon(varname)) != nil
 }
 
 // IsUsedAtLoadTime returns true if the variable is used at load time
 // somewhere.
 func (s *Scope) IsUsedAtLoadTime(varname string) bool {
-	return s.v(varname).usedAtLoadTime
+	v := s.vs[varname]
+	return v != nil && v.usedAtLoadTime
 }
 
 // FirstDefinition returns the line in which the variable has been defined first.
@@ -782,7 +799,12 @@ func (s *Scope) IsUsedAtLoadTime(varname string) bool {
 // round: the including file sets a value first, and the included file then
 // assigns a default value using ?=.
 func (s *Scope) FirstDefinition(varname string) *MkLine {
-	mkline := s.v(varname).firstDef
+	v := s.vs[varname]
+	if v == nil {
+		return nil
+	}
+
+	mkline := v.firstDef
 	if mkline != nil && mkline.IsVarassign() {
 		lastLine := s.LastDefinition(varname)
 		if trace.Tracing && lastLine != mkline {
@@ -803,7 +825,12 @@ func (s *Scope) FirstDefinition(varname string) *MkLine {
 // round: the including file sets a value first, and the included file then
 // assigns a default value using ?=.
 func (s *Scope) LastDefinition(varname string) *MkLine {
-	mkline := s.v(varname).lastDef
+	v := s.vs[varname]
+	if v == nil {
+		return nil
+	}
+
+	mkline := v.lastDef
 	if mkline != nil && mkline.IsVarassign() {
 		return mkline
 	}
@@ -814,12 +841,17 @@ func (s *Scope) LastDefinition(varname string) *MkLine {
 // variable assignments. These are ignored by bmake but used heavily in
 // mk/defaults/mk.conf for documentation.
 func (s *Scope) Commented(varname string) *MkLine {
-	var mklines []*MkLine
-	if first := s.v(varname).firstDef; first != nil {
-		mklines = append(mklines, first)
+	v := s.vs[varname]
+	if v == nil {
+		return nil
 	}
-	if last := s.v(varname).lastDef; last != nil {
-		mklines = append(mklines, last)
+
+	mklines := make([]*MkLine, 0, 2)
+	if v.firstDef != nil {
+		mklines = append(mklines, v.firstDef)
+	}
+	if v.lastDef != nil {
+		mklines = append(mklines, v.lastDef)
 	}
 
 	for _, mkline := range mklines {
@@ -838,7 +870,11 @@ func (s *Scope) Commented(varname string) *MkLine {
 }
 
 func (s *Scope) FirstUse(varname string) *MkLine {
-	return s.v(varname).used
+	v := s.vs[varname]
+	if v == nil {
+		return nil
+	}
+	return v.used
 }
 
 // LastValue returns the value from the last variable definition.
@@ -868,14 +904,8 @@ func (s *Scope) LastValueFound(varname string) (value string, found bool, indete
 	return v.fallback, v.fallback != "", v.indeterminate
 }
 
-func (s *Scope) DefineAll(other Scope) {
-	var varnames []string
-	for varname := range other.vs {
-		varnames = append(varnames, varname)
-	}
-	sort.Strings(varnames)
-
-	for _, varname := range varnames {
+func (s *Scope) DefineAll(other *Scope) {
+	for _, varname := range other.varnames() {
 		v := other.vs[varname]
 		if v.firstDef != nil {
 			s.Define(varname, v.firstDef)
diff --git a/pkgtools/pkglint/files/util_test.go b/pkgtools/pkglint/files/util_test.go
index f161a532232..9d178fafd52 100644
--- a/pkgtools/pkglint/files/util_test.go
+++ b/pkgtools/pkglint/files/util_test.go
@@ -737,12 +737,12 @@ func (s *Suite) Test_Scope_DefineAll(c *check.C) {
 	src := NewScope()
 
 	dst := NewScope()
-	dst.DefineAll(src)
+	dst.DefineAll(&src)
 
 	c.Check(dst.vs, check.HasLen, 0)
 
 	src.Define("VAR", t.NewMkLine("file.mk", 1, "VAR=value"))
-	dst.DefineAll(src)
+	dst.DefineAll(&src)
 
 	t.CheckEquals(dst.IsDefined("VAR"), true)
 }
diff --git a/pkgtools/pkglint/files/var.go b/pkgtools/pkglint/files/var.go
index 0fd9319fae4..b0b6857497e 100644
--- a/pkgtools/pkglint/files/var.go
+++ b/pkgtools/pkglint/files/var.go
@@ -267,12 +267,15 @@ func (v *Var) updateConstantValue(mkline *MkLine) {
 		}
 
 	case opAssignAppend:
-		v.constantValue += " " + value
+		if v.constantState != 0 {
+			v.constantValue += " "
+		}
+		v.constantValue += value
 
 	default:
 		v.constantState = 3
 		v.constantValue = ""
 	}
 
-	v.constantState = [...]uint8{1, 1, 3, 3}[v.constantState]
+	v.constantState |= 1
 }
diff --git a/pkgtools/pkglint/files/var_test.go b/pkgtools/pkglint/files/var_test.go
index 5d27f882575..418a3a21589 100644
--- a/pkgtools/pkglint/files/var_test.go
+++ b/pkgtools/pkglint/files/var_test.go
@@ -137,11 +137,11 @@ func (s *Suite) Test_Var_ConstantValue__append(c *check.C) {
 
 	v.Write(t.NewMkLine("write.mk", 123, "VARNAME+=\tvalue"), false)
 
-	t.CheckEquals(v.ConstantValue(), " value")
+	t.CheckEquals(v.ConstantValue(), "value")
 
 	v.Write(t.NewMkLine("write.mk", 124, "VARNAME+=\tappended"), false)
 
-	t.CheckEquals(v.ConstantValue(), " value appended")
+	t.CheckEquals(v.ConstantValue(), "value appended")
 }
 
 func (s *Suite) Test_Var_ConstantValue__eval(c *check.C) {
diff --git a/pkgtools/pkglint/files/vartypecheck_test.go b/pkgtools/pkglint/files/vartypecheck_test.go
index f429a2940d2..8c316ee1793 100644
--- a/pkgtools/pkglint/files/vartypecheck_test.go
+++ b/pkgtools/pkglint/files/vartypecheck_test.go
@@ -503,6 +503,8 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__smaller_version(c *check.C)
 	t.CheckOutputLines(
 		"NOTE: Makefile:21: The requirement >=1.0pkg is already guaranteed "+
 			"by the >=1.3api from ../../category/lib/buildlink3.mk:12.",
+		"ERROR: Makefile:22: Packages must only require API versions, "+
+			"not ABI versions of dependencies.",
 		"NOTE: Makefile:22: The requirement >=1.1pkg is already guaranteed "+
 			"by the >=1.4abi from ../../category/lib/buildlink3.mk:13.")
 }
@@ -526,6 +528,8 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__different_operators(c *chec
 	t.CheckOutputLines(
 		"NOTE: Makefile:21: The requirement >=1.0pkg is already guaranteed "+
 			"by the >1.3api from ../../category/lib/buildlink3.mk:12.",
+		"ERROR: Makefile:22: Packages must only require API versions, "+
+			"not ABI versions of dependencies.",
 		"NOTE: Makefile:22: The requirement >=1.1pkg is already guaranteed "+
 			"by the >1.4abi from ../../category/lib/buildlink3.mk:13.")
 }
@@ -549,6 +553,8 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__additional_greater(c *check
 	t.CheckOutputLines(
 		"NOTE: Makefile:21: The requirement >1.0pkg is already guaranteed "+
 			"by the >=1.3api from ../../category/lib/buildlink3.mk:12.",
+		"ERROR: Makefile:22: Packages must only require API versions, "+
+			"not ABI versions of dependencies.",
 		"NOTE: Makefile:22: The requirement >1.1pkg is already guaranteed "+
 			"by the >=1.4abi from ../../category/lib/buildlink3.mk:13.")
 }
@@ -570,8 +576,10 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__upper_limit(c *check.C) {
 	G.checkdirPackage(".")
 
 	// If the additional constraint doesn't have a lower bound,
-	// there is nothing to compare and warn about.
-	t.CheckOutputEmpty()
+	// there are no version numbers to compare and warn about.
+	t.CheckOutputLines(
+		"ERROR: Makefile:22: Packages must only require API versions, " +
+			"not ABI versions of dependencies.")
 }
 
 // Having an upper bound for a library dependency is unusual.
@@ -593,8 +601,10 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__upper_limit_in_buildlink3(c
 	G.checkdirPackage(".")
 
 	// If the additional constraint doesn't have a lower bound,
-	// there is nothing to compare and warn about.
-	t.CheckOutputEmpty()
+	// there are no version numbers to compare and warn about.
+	t.CheckOutputLines(
+		"ERROR: Makefile:22: Packages must only require API versions, " +
+			"not ABI versions of dependencies.")
 }
 
 func (s *Suite) Test_VartypeCheck_DependencyPattern__API_ABI(c *check.C) {
@@ -628,7 +638,9 @@ func (s *Suite) Test_VartypeCheck_DependencyPattern__ABI_API(c *check.C) {
 
 	G.checkdirPackage(".")
 
-	t.CheckOutputEmpty()
+	t.CheckOutputLines(
+		"ERROR: Makefile:21: Packages must only require API versions, " +
+			"not ABI versions of dependencies.")
 }
 
 func (s *Suite) Test_VartypeCheck_DependencyWithPath(c *check.C) {