1 files changed, 158 insertions, 0 deletions
diff --git a/src/pkg/go/token/position_test.go b/src/pkg/go/token/position_test.go
new file mode 100644
index 000000000..1cffcc3c2
--- /dev/null
+++ b/src/pkg/go/token/position_test.go
@@ -0,0 +1,158 @@
+// Copyright 2010 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 token
+
+import (
+	"fmt"
+	"testing"
+)
+
+
+func checkPos(t *testing.T, msg string, p, q Position) {
+	if p.Filename != q.Filename {
+		t.Errorf("%s: expected filename = %q; got %q", msg, q.Filename, p.Filename)
+	}
+	if p.Offset != q.Offset {
+		t.Errorf("%s: expected offset = %d; got %d", msg, q.Offset, p.Offset)
+	}
+	if p.Line != q.Line {
+		t.Errorf("%s: expected line = %d; got %d", msg, q.Line, p.Line)
+	}
+	if p.Column != q.Column {
+		t.Errorf("%s: expected column = %d; got %d", msg, q.Column, p.Column)
+	}
+}
+
+
+func TestNoPos(t *testing.T) {
+	if NoPos.IsValid() {
+		t.Errorf("NoPos should not be valid")
+	}
+	var fset *FileSet
+	checkPos(t, "nil NoPos", fset.Position(NoPos), Position{})
+	fset = NewFileSet()
+	checkPos(t, "fset NoPos", fset.Position(NoPos), Position{})
+}
+
+
+var tests = []struct {
+	filename string
+	size     int
+	lines    []int
+}{
+	{"a", 0, []int{}},
+	{"b", 5, []int{0}},
+	{"c", 10, []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}},
+	{"d", 100, []int{0, 5, 10, 20, 30, 70, 71, 72, 80, 85, 90, 99}},
+	{"e", 777, []int{0, 80, 100, 120, 130, 180, 267, 455, 500, 567, 620}},
+}
+
+
+func linecol(lines []int, offs int) (int, int) {
+	prevLineOffs := 0
+	for line, lineOffs := range lines {
+		if offs < lineOffs {
+			return line, offs - prevLineOffs + 1
+		}
+		prevLineOffs = lineOffs
+	}
+	return len(lines), offs - prevLineOffs + 1
+}
+
+
+func verifyPositions(t *testing.T, fset *FileSet, f *File, lines []int) {
+	for offs := 0; offs < f.Size(); offs++ {
+		p := f.Pos(offs)
+		offs2 := f.Offset(p)
+		if offs2 != offs {
+			t.Errorf("%s, Offset: expected offset %d; got %d", f.Name(), offs, offs2)
+		}
+		line, col := linecol(lines, offs)
+		msg := fmt.Sprintf("%s (offs = %d, p = %d)", f.Name(), offs, p)
+		checkPos(t, msg, f.Position(f.Pos(offs)), Position{f.Name(), offs, line, col})
+		checkPos(t, msg, fset.Position(p), Position{f.Name(), offs, line, col})
+	}
+}
+
+
+func TestPositions(t *testing.T) {
+	const delta = 7 // a non-zero base offset increment
+	fset := NewFileSet()
+	for _, test := range tests {
+		// add file and verify name and size
+		f := fset.AddFile(test.filename, fset.Base()+delta, test.size)
+		if f.Name() != test.filename {
+			t.Errorf("expected filename %q; got %q", test.filename, f.Name())
+		}
+		if f.Size() != test.size {
+			t.Errorf("%s: expected file size %d; got %d", f.Name(), test.size, f.Size())
+		}
+		if fset.File(f.Pos(0)) != f {
+			t.Errorf("%s: f.Pos(0) was not found in f", f.Name())
+		}
+
+		// add lines individually and verify all positions
+		for i, offset := range test.lines {
+			f.AddLine(offset)
+			if f.LineCount() != i+1 {
+				t.Errorf("%s, AddLine: expected line count %d; got %d", f.Name(), i+1, f.LineCount())
+			}
+			// adding the same offset again should be ignored
+			f.AddLine(offset)
+			if f.LineCount() != i+1 {
+				t.Errorf("%s, AddLine: expected unchanged line count %d; got %d", f.Name(), i+1, f.LineCount())
+			}
+			verifyPositions(t, fset, f, test.lines[0:i+1])
+		}
+
+		// add lines at once and verify all positions
+		ok := f.SetLines(test.lines)
+		if !ok {
+			t.Errorf("%s: SetLines failed", f.Name())
+		}
+		if f.LineCount() != len(test.lines) {
+			t.Errorf("%s, SetLines: expected line count %d; got %d", f.Name(), len(test.lines), f.LineCount())
+		}
+		verifyPositions(t, fset, f, test.lines)
+	}
+}
+
+
+func TestLineInfo(t *testing.T) {
+	fset := NewFileSet()
+	f := fset.AddFile("foo", fset.Base(), 500)
+	lines := []int{0, 42, 77, 100, 210, 220, 277, 300, 333, 401}
+	// add lines individually and provide alternative line information
+	for _, offs := range lines {
+		f.AddLine(offs)
+		f.AddLineInfo(offs, "bar", 42)
+	}
+	// verify positions for all offsets
+	for offs := 0; offs <= f.Size(); offs++ {
+		p := f.Pos(offs)
+		_, col := linecol(lines, offs)
+		msg := fmt.Sprintf("%s (offs = %d, p = %d)", f.Name(), offs, p)
+		checkPos(t, msg, f.Position(f.Pos(offs)), Position{"bar", offs, 42, col})
+		checkPos(t, msg, fset.Position(p), Position{"bar", offs, 42, col})
+	}
+}
+
+
+func TestFiles(t *testing.T) {
+	fset := NewFileSet()
+	for i, test := range tests {
+		fset.AddFile(test.filename, fset.Base(), test.size)
+		j := 0
+		for g := range fset.Files() {
+			if g.Name() != tests[j].filename {
+				t.Errorf("expected filename = %s; got %s", tests[j].filename, g.Name())
+			}
+			j++
+		}
+		if j != i+1 {
+			t.Errorf("expected %d files; got %d", i+1, j)
+		}
+	}
+}