1 files changed, 39 insertions, 8 deletions

diff --git a/src/pkg/go/token/position_test.go b/src/pkg/go/token/position_test.go
index 1cffcc3c2..979c9b1e8 100644
--- a/src/pkg/go/token/position_test.go
+++ b/src/pkg/go/token/position_test.go
@@ -39,14 +39,18 @@ func TestNoPos(t *testing.T) {
 
 var tests = []struct {
 	filename string
+	source   []byte // may be nil
 	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}},
+	{"a", []byte{}, 0, []int{}},
+	{"b", []byte("01234"), 5, []int{0}},
+	{"c", []byte("\n\n\n\n\n\n\n\n\n"), 9, []int{0, 1, 2, 3, 4, 5, 6, 7, 8}},
+	{"d", nil, 100, []int{0, 5, 10, 20, 30, 70, 71, 72, 80, 85, 90, 99}},
+	{"e", nil, 777, []int{0, 80, 100, 120, 130, 180, 267, 455, 500, 567, 620}},
+	{"f", []byte("package p\n\nimport \"fmt\""), 23, []int{0, 10, 11}},
+	{"g", []byte("package p\n\nimport \"fmt\"\n"), 24, []int{0, 10, 11}},
+	{"h", []byte("package p\n\nimport \"fmt\"\n "), 25, []int{0, 10, 11, 24}},
 }
 
 
@@ -77,10 +81,26 @@ func verifyPositions(t *testing.T, fset *FileSet, f *File, lines []int) {
 }
 
 
+func makeTestSource(size int, lines []int) []byte {
+	src := make([]byte, size)
+	for _, offs := range lines {
+		if offs > 0 {
+			src[offs-1] = '\n'
+		}
+	}
+	return src
+}
+
+
 func TestPositions(t *testing.T) {
 	const delta = 7 // a non-zero base offset increment
 	fset := NewFileSet()
 	for _, test := range tests {
+		// verify consistency of test case
+		if test.source != nil && len(test.source) != test.size {
+			t.Errorf("%s: inconsistent test case: expected file size %d; got %d", test.filename, test.size, len(test.source))
+		}
+
 		// add file and verify name and size
 		f := fset.AddFile(test.filename, fset.Base()+delta, test.size)
 		if f.Name() != test.filename {
@@ -107,15 +127,26 @@ func TestPositions(t *testing.T) {
 			verifyPositions(t, fset, f, test.lines[0:i+1])
 		}
 
-		// add lines at once and verify all positions
-		ok := f.SetLines(test.lines)
-		if !ok {
+		// add lines with SetLines and verify all positions
+		if ok := f.SetLines(test.lines); !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)
+
+		// add lines with SetLinesForContent and verify all positions
+		src := test.source
+		if src == nil {
+			// no test source available - create one from scratch
+			src = makeTestSource(test.size, test.lines)
+		}
+		f.SetLinesForContent(src)
+		if f.LineCount() != len(test.lines) {
+			t.Errorf("%s, SetLinesForContent: expected line count %d; got %d", f.Name(), len(test.lines), f.LineCount())
+		}
+		verifyPositions(t, fset, f, test.lines)
 	}
 }