From: Dmitri Shuralyov <shurcooL@gmail.com>
Date: Fri, 22 Aug 2014 17:18:00 +0000 (-0700)
Subject: cmd/gofmt: fix error on partial Go code ending with line comment.
X-Git-Tag: go1.4beta1~750
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=9368d6ccbfe57bc54b433b22b2008d3c4faf086d;p=gostls13.git

cmd/gofmt: fix error on partial Go code ending with line comment.

Fix issue by always appending newline after user input, before
the closing curly bracket. The adjust func is modified to remove
this new newline.

Add test case (it fails before CL, passes after).

Fixes #8411.

LGTM=gri
R=golang-codereviews, bradfitz, josharian, gri
CC=golang-codereviews
https://golang.org/cl/124700043
---

diff --git a/src/cmd/gofmt/gofmt.go b/src/cmd/gofmt/gofmt.go
index 576cae5228..f7d30d8405 100644
--- a/src/cmd/gofmt/gofmt.go
+++ b/src/cmd/gofmt/gofmt.go
@@ -277,14 +277,14 @@ func parse(fset *token.FileSet, filename string, src []byte, stdin bool) (*ast.F
 	// into a function body.  This handles expressions too.
 	// Insert using a ;, not a newline, so that the line numbers
 	// in fsrc match the ones in src.
-	fsrc := append(append([]byte("package p; func _() {"), src...), '}')
+	fsrc := append(append([]byte("package p; func _() {"), src...), '\n', '}')
 	file, err = parser.ParseFile(fset, filename, fsrc, parserMode)
 	if err == nil {
 		adjust := func(orig, src []byte) []byte {
 			// Remove the wrapping.
 			// Gofmt has turned the ; into a \n\n.
 			src = src[len("package p\n\nfunc _() {"):]
-			src = src[:len(src)-len("}\n")]
+			src = src[:len(src)-len("\n}\n")]
 			// Gofmt has also indented the function body one level.
 			// Remove that indent.
 			src = bytes.Replace(src, []byte("\n\t"), []byte("\n"), -1)
diff --git a/src/cmd/gofmt/testdata/stdin5.golden b/src/cmd/gofmt/testdata/stdin5.golden
new file mode 100644
index 0000000000..31ce6b2485
--- /dev/null
+++ b/src/cmd/gofmt/testdata/stdin5.golden
@@ -0,0 +1,3 @@
+//gofmt -stdin
+
+i := 5 // Line comment without newline.
\ No newline at end of file
diff --git a/src/cmd/gofmt/testdata/stdin5.input b/src/cmd/gofmt/testdata/stdin5.input
new file mode 100644
index 0000000000..0a7c97d180
--- /dev/null
+++ b/src/cmd/gofmt/testdata/stdin5.input
@@ -0,0 +1,3 @@
+//gofmt -stdin
+
+i  :=5// Line comment without newline.
\ No newline at end of file