caddyconfig: Don't start comments in middle of tokens (#3267)

* caddyconfig: Only parse # as start of comment if preceded by space

* caddyconfig: Simplify # logic using len(val), add a test

4 files changed, 28 insertions, 6 deletions

diff --git a/caddyconfig/caddyfile/formatter.go b/caddyconfig/caddyfile/formatter.go
index 2c97f3b..6270541 100644
--- a/caddyconfig/caddyfile/formatter.go
+++ b/caddyconfig/caddyfile/formatter.go
@@ -131,9 +131,6 @@ func Format(input []byte) []byte {
 		//////////////////////////////////////////////////////////
 
 		if ch == '#' {
-			if !spacePrior && !beginningOfLine {
-				write(' ')
-			}
 			comment = true
 		}
 
diff --git a/caddyconfig/caddyfile/formatter_test.go b/caddyconfig/caddyfile/formatter_test.go
index 25bd7fa..6751eca 100644
--- a/caddyconfig/caddyfile/formatter_test.go
+++ b/caddyconfig/caddyfile/formatter_test.go
@@ -201,7 +201,7 @@ c
 }
 
 d {
-	e #f
+	e#f
 	# g
 }
 
@@ -229,7 +229,7 @@ bar"
 j {
 "\"k\" l m"
 }`,
-			expect: `"a \"b\" " #c
+			expect: `"a \"b\" "#c
 d
 
 e {
@@ -305,6 +305,11 @@ bar "{\"key\":34}"`,
 
 baz`,
 		},
+		{
+			description: "hash within string is not a comment",
+			input:       `redir / /some/#/path`,
+			expect:      `redir / /some/#/path`,
+		},
 	} {
 		// the formatter should output a trailing newline,
 		// even if the tests aren't written to expect that
diff --git a/caddyconfig/caddyfile/lexer.go b/caddyconfig/caddyfile/lexer.go
index d9968ff..568d15c 100755
--- a/caddyconfig/caddyfile/lexer.go
+++ b/caddyconfig/caddyfile/lexer.go
@@ -141,7 +141,7 @@ func (l *lexer) next() bool {
 			continue
 		}
 
-		if ch == '#' {
+		if ch == '#' && len(val) == 0 {
 			comment = true
 		}
 		if comment {
diff --git a/caddyconfig/caddyfile/lexer_test.go b/caddyconfig/caddyfile/lexer_test.go
index 734006e..c8c941a 100755
--- a/caddyconfig/caddyfile/lexer_test.go
+++ b/caddyconfig/caddyfile/lexer_test.go
@@ -78,6 +78,26 @@ func TestLexer(t *testing.T) {
 			},
 		},
 		{
+			input: `host:123 {
+						# hash inside string is not a comment
+						redir / /some/#/path
+					}`,
+			expected: []Token{
+				{Line: 1, Text: "host:123"},
+				{Line: 1, Text: "{"},
+				{Line: 3, Text: "redir"},
+				{Line: 3, Text: "/"},
+				{Line: 3, Text: "/some/#/path"},
+				{Line: 4, Text: "}"},
+			},
+		},
+		{
+			input: "# comment at beginning of file\n# comment at beginning of line\nhost:123",
+			expected: []Token{
+				{Line: 3, Text: "host:123"},
+			},
+		},
+		{
 			input: `a "quoted value" b
 					foobar`,
 			expected: []Token{