go/printer, gofmt: trim trailing whitespace in comments

Also: updated go fix testcases to pass tests.

Fixes issue 4310.

R=r
CC=golang-dev
http://codereview.appspot.com/6810055

2 files changed, 19 insertions, 2 deletions

diff --git a/src/pkg/go/printer/testdata/comments.golden b/src/pkg/go/printer/testdata/comments.golden
index d9aa2d82f..610a42a68 100644
--- a/src/pkg/go/printer/testdata/comments.golden
+++ b/src/pkg/go/printer/testdata/comments.golden
@@ -529,7 +529,7 @@ func _() {
 }
 
 func _() {
-	var a = []int{1, 2}// jasldf 
+	var a = []int{1, 2}// jasldf
 
 	_ = a
 }
@@ -626,4 +626,13 @@ func _() {
 	var lflag bool		// -l			- disable line directives
 }
 
+// Trailing white space in comments should be trimmed
+func _() {
+	// This comment has 4 blanks following that should be trimmed:
+	/* Each line of this comment has blanks or tabs following that should be trimmed:
+	   line 2:
+	   line 3:
+	*/
+}
+
 /* This comment is the last entry in this file. It must be printed and should be followed by a newline */
diff --git a/src/pkg/go/printer/testdata/comments.input b/src/pkg/go/printer/testdata/comments.input
index 6084b3fe4..d121dd4be 100644
--- a/src/pkg/go/printer/testdata/comments.input
+++ b/src/pkg/go/printer/testdata/comments.input
@@ -534,7 +534,7 @@ func _() {
 }
 
 func _() {
-	var a = []int{1, 2, // jasldf 
+	var a = []int{1, 2, // jasldf
 	}
 	_ = a
 }
@@ -630,5 +630,13 @@ var	vflag		string				// -v [y.output]	- y.output file
 var	lflag		bool				// -l			- disable line directives
 }
 
+// Trailing white space in comments should be trimmed
+func _() {
+// This comment has 4 blanks following that should be trimmed:    
+/* Each line of this comment has blanks or tabs following that should be trimmed:	
+   line 2:    
+   line 3:    			
+*/
+}
 
 /* This comment is the last entry in this file. It must be printed and should be followed by a newline */