1 files changed, 226 insertions, 0 deletions
diff --git a/src/go/build/read_test.go b/src/go/build/read_test.go
new file mode 100644
index 000000000..2dcc1208f
--- /dev/null
+++ b/src/go/build/read_test.go
@@ -0,0 +1,226 @@
+// Copyright 2012 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package build
+
+import (
+	"io"
+	"strings"
+	"testing"
+)
+
+const quote = "`"
+
+type readTest struct {
+	// Test input contains ℙ where readImports should stop.
+	in  string
+	err string
+}
+
+var readImportsTests = []readTest{
+	{
+		`package p`,
+		"",
+	},
+	{
+		`package p; import "x"`,
+		"",
+	},
+	{
+		`package p; import . "x"`,
+		"",
+	},
+	{
+		`package p; import "x";ℙvar x = 1`,
+		"",
+	},
+	{
+		`package p
+		
+		// comment
+		
+		import "x"
+		import _ "x"
+		import a "x"
+		
+		/* comment */
+		
+		import (
+			"x" /* comment */
+			_ "x"
+			a "x" // comment
+			` + quote + `x` + quote + `
+			_ /*comment*/ ` + quote + `x` + quote + `
+			a ` + quote + `x` + quote + `
+		)
+		import (
+		)
+		import ()
+		import()import()import()
+		import();import();import()
+		
+		ℙvar x = 1
+		`,
+		"",
+	},
+}
+
+var readCommentsTests = []readTest{
+	{
+		`ℙpackage p`,
+		"",
+	},
+	{
+		`ℙpackage p; import "x"`,
+		"",
+	},
+	{
+		`ℙpackage p; import . "x"`,
+		"",
+	},
+	{
+		`// foo
+
+		/* bar */
+
+		/* quux */ // baz
+		
+		/*/ zot */
+
+		// asdf
+		ℙHello, world`,
+		"",
+	},
+}
+
+func testRead(t *testing.T, tests []readTest, read func(io.Reader) ([]byte, error)) {
+	for i, tt := range tests {
+		var in, testOut string
+		j := strings.Index(tt.in, "ℙ")
+		if j < 0 {
+			in = tt.in
+			testOut = tt.in
+		} else {
+			in = tt.in[:j] + tt.in[j+len("ℙ"):]
+			testOut = tt.in[:j]
+		}
+		r := strings.NewReader(in)
+		buf, err := read(r)
+		if err != nil {
+			if tt.err == "" {
+				t.Errorf("#%d: err=%q, expected success (%q)", i, err, string(buf))
+				continue
+			}
+			if !strings.Contains(err.Error(), tt.err) {
+				t.Errorf("#%d: err=%q, expected %q", i, err, tt.err)
+				continue
+			}
+			continue
+		}
+		if err == nil && tt.err != "" {
+			t.Errorf("#%d: success, expected %q", i, tt.err)
+			continue
+		}
+
+		out := string(buf)
+		if out != testOut {
+			t.Errorf("#%d: wrong output:\nhave %q\nwant %q\n", i, out, testOut)
+		}
+	}
+}
+
+func TestReadImports(t *testing.T) {
+	testRead(t, readImportsTests, func(r io.Reader) ([]byte, error) { return readImports(r, true) })
+}
+
+func TestReadComments(t *testing.T) {
+	testRead(t, readCommentsTests, readComments)
+}
+
+var readFailuresTests = []readTest{
+	{
+		`package`,
+		"syntax error",
+	},
+	{
+		"package p\n\x00\nimport `math`\n",
+		"unexpected NUL in input",
+	},
+	{
+		`package p; import`,
+		"syntax error",
+	},
+	{
+		`package p; import "`,
+		"syntax error",
+	},
+	{
+		"package p; import ` \n\n",
+		"syntax error",
+	},
+	{
+		`package p; import "x`,
+		"syntax error",
+	},
+	{
+		`package p; import _`,
+		"syntax error",
+	},
+	{
+		`package p; import _ "`,
+		"syntax error",
+	},
+	{
+		`package p; import _ "x`,
+		"syntax error",
+	},
+	{
+		`package p; import .`,
+		"syntax error",
+	},
+	{
+		`package p; import . "`,
+		"syntax error",
+	},
+	{
+		`package p; import . "x`,
+		"syntax error",
+	},
+	{
+		`package p; import (`,
+		"syntax error",
+	},
+	{
+		`package p; import ("`,
+		"syntax error",
+	},
+	{
+		`package p; import ("x`,
+		"syntax error",
+	},
+	{
+		`package p; import ("x"`,
+		"syntax error",
+	},
+}
+
+func TestReadFailures(t *testing.T) {
+	// Errors should be reported (true arg to readImports).
+	testRead(t, readFailuresTests, func(r io.Reader) ([]byte, error) { return readImports(r, true) })
+}
+
+func TestReadFailuresIgnored(t *testing.T) {
+	// Syntax errors should not be reported (false arg to readImports).
+	// Instead, entire file should be the output and no error.
+	// Convert tests not to return syntax errors.
+	tests := make([]readTest, len(readFailuresTests))
+	copy(tests, readFailuresTests)
+	for i := range tests {
+		tt := &tests[i]
+		if !strings.Contains(tt.err, "NUL") {
+			tt.err = ""
+		}
+	}
+	testRead(t, tests, func(r io.Reader) ([]byte, error) { return readImports(r, false) })
+}