allow escaped double-quote in "raw" string literals

Fixes #12

Author: speter

issues_test.go

@@ -92,3 +92,19 @@ func TestIssue11(t *testing.T) {
 		}
 	}
 }
+
+// Escaped double quote should be supported in "raw" string literals
+func TestIssue12(t *testing.T) {
+	var c struct {
+		Section struct {
+			Name string
+		}
+	}
+	err := ReadFileInto(&c, "testdata/issue12.gcfg")
+	if err != nil {
+		t.Fatalf("fail: want ok, got error %v", err)
+	}
+	if c.Section.Name != `"value"` {
+		t.Errorf("fail: want `\"value\"`, got %q", c.Section.Name)
+	}
+}

read_test.go

@@ -124,6 +124,7 @@ var readtests = []struct {
 	{"[section]\nname=\"va\\\"lue\"", &cBasic{Section: cBasicS1{Name: "va\"lue"}}, true},
 	{"[section]\nname=\"va\\nlue\"", &cBasic{Section: cBasicS1{Name: "va\nlue"}}, true},
 	{"[section]\nname=\"va\\tlue\"", &cBasic{Section: cBasicS1{Name: "va\tlue"}}, true},
+	{"[section]\nname=\\\"value\\\"", &cBasic{Section: cBasicS1{Name: `"value"`}}, true},
 	{"\n[section]\nname=\\", &cBasic{}, false},
 	{"\n[section]\nname=\\a", &cBasic{}, false},
 	{"\n[section]\nname=\"val\\a\"", &cBasic{}, false},

scanner/scanner.go

@@ -231,8 +231,8 @@ loop:
 				hasCR = true
 				s.next()
 			}
-			if s.ch != '\n' {
-				s.error(offs, "unquoted '\\' must be followed by new line")
+			if s.ch != '\n' && s.ch != '"' {
+				s.error(offs, "unquoted '\\' must be followed by new line or double quote")
 				break loop
 			}
 			s.next()

scanner/scanner_test.go

@@ -80,6 +80,7 @@ var tokens = [...]elt{
 	{token.STRING, `"foo" "bar"`, literal, "=", " "},
 	{token.STRING, "foo\\\nbar", literal, "=", ""},
 	{token.STRING, "foo\\\r\nbar", literal, "=", ""},
+	{token.STRING, `\"foobar\"`, literal, "=", ""},
 }
 
 const whitespace = "  \t  \n\n\n" // to separate tokens
@@ -381,8 +382,8 @@ var errors = []struct {
 	{"\"\n", token.STRING, 0, "string not terminated"},
 	{`="`, token.STRING, 1, "string not terminated"},
 	{"=\"\n", token.STRING, 1, "string not terminated"},
-	{"=\\", token.STRING, 1, "unquoted '\\' must be followed by new line"},
-	{"=\\\r", token.STRING, 1, "unquoted '\\' must be followed by new line"},
+	{"=\\", token.STRING, 1, "unquoted '\\' must be followed by new line or double quote"},
+	{"=\\\r", token.STRING, 1, "unquoted '\\' must be followed by new line or double quote"},
 	{`"\z"`, token.STRING, 2, "unknown escape sequence"},
 	{`"\a"`, token.STRING, 2, "unknown escape sequence"},
 	{`"\b"`, token.STRING, 2, "unknown escape sequence"},

testdata/issue12.gcfg

@@ -0,0 +1,2 @@
+[section]
+	name = \"value\"