parse quotes from file

Author: brian316

pkg/kvfile/kvfile.go

@@ -15,8 +15,8 @@
 //
 // # Interpolation, substitution, and escaping
 //
-// Both keys and values are used as-is; no interpolation, substitution or
-// escaping is supported, and quotes are considered part of the key or value.
+// Both keys and values are used as-is; no interpolation or substitution is supported.
+// Quotes around values are removed if the value starts and ends with the same quote character.
 // Whitespace in values (including leading and trailing) is preserved. Given
 // that the file format is line-delimited, neither key, nor value, can contain
 // newlines.
@@ -78,6 +78,20 @@ func ParseFromReader(r io.Reader, lookupFn func(key string) (value string, found
 
 const whiteSpaces = " \t"
 
+// trimQuotes removes the quotes from a string if the string starts and ends with the same quote character.
+func trimQuotes(value string) string {
+	if len(value) < 2 {
+		return value
+	}
+	lastIndex := len(value) - 1
+	for _, char := range []byte{'\'', '"'} {
+		if value[0] == char && value[lastIndex] == char {
+			return value[1:lastIndex]
+		}
+	}
+	return value
+}
+
 func parseKeyValueFile(r io.Reader, lookupFn func(string) (string, bool)) ([]string, error) {
 	lines := []string{}
 	scanner := bufio.NewScanner(r)
@@ -113,15 +127,22 @@ func parseKeyValueFile(r io.Reader, lookupFn func(string) (string, bool)) ([]str
 		}
 
 		if hasValue {
-			// key/value pair is valid and has a value; add the line as-is.
-			lines = append(lines, line)
+			// key/value pair is valid and has a value
+			// Split the line to get the key and value
+			key, value, _ := strings.Cut(line, "=")
+			// Trim quotes from the value
+			value = trimQuotes(value)
+			// Reconstruct the line with the trimmed value
+			lines = append(lines, key+"="+value)
 			continue
 		}
 
 		if lookupFn != nil {
 			// No value given; try to look up the value. The value may be
 			// empty but if no value is found, the key is omitted.
 			if value, found := lookupFn(line); found {
+				// Trim quotes from the value
+				value = trimQuotes(value)
 				lines = append(lines, key+"="+value)
 			}
 		}

pkg/kvfile/kvfile_test.go

@@ -24,9 +24,12 @@ VAR=VAR_VALUE
 EMPTY_VAR=
 UNDEFINED_VAR
 DEFINED_VAR
+QUOTED_VAR
+QUOTED_VALUE="this should be quoted"
 `
 	vars := map[string]string{
 		"DEFINED_VAR": "defined-value",
+		"QUOTED_VAR":  "\"quoted value\"",
 	}
 	lookupFn := func(name string) (string, bool) {
 		v, ok := vars[name]
@@ -40,7 +43,13 @@ DEFINED_VAR
 	variables, err := Parse(fileName, lookupFn)
 	assert.NilError(t, err)
 
-	expectedLines := []string{"VAR=VAR_VALUE", "EMPTY_VAR=", "DEFINED_VAR=defined-value"}
+	expectedLines := []string{
+		"VAR=VAR_VALUE",
+		"EMPTY_VAR=",
+		"DEFINED_VAR=defined-value",
+		"QUOTED_VAR=quoted value",
+		"QUOTED_VALUE=this should be quoted",
+	}
 	assert.Check(t, is.DeepEqual(variables, expectedLines))
 }
 
@@ -118,9 +127,11 @@ VAR=VAR_VALUE
 EMPTY_VAR=
 UNDEFINED_VAR
 DEFINED_VAR
+QUOTED_VAR
 `
 	vars := map[string]string{
 		"DEFINED_VAR": "defined-value",
+		"QUOTED_VAR":  "\"quoted value\"",
 	}
 	lookupFn := func(name string) (string, bool) {
 		v, ok := vars[name]
@@ -130,7 +141,12 @@ DEFINED_VAR
 	variables, err := ParseFromReader(strings.NewReader(content), lookupFn)
 	assert.NilError(t, err)
 
-	expectedLines := []string{"VAR=VAR_VALUE", "EMPTY_VAR=", "DEFINED_VAR=defined-value"}
+	expectedLines := []string{
+		"VAR=VAR_VALUE",
+		"EMPTY_VAR=",
+		"DEFINED_VAR=defined-value",
+		"QUOTED_VAR=quoted value",
+	}
 	assert.Check(t, is.DeepEqual(variables, expectedLines))
 }
 
@@ -143,3 +159,29 @@ func TestParseFromReaderWithNoName(t *testing.T) {
 	const expectedMessage = "no variable name on line '=blank variable names are an error case'"
 	assert.Check(t, is.ErrorContains(err, expectedMessage))
 }
+
+// Test ParseFromReader with quoted values
+func TestParseFromReaderWithQuotes(t *testing.T) {
+	content := `# Test with quotes
+DOUBLE_QUOTES="double quoted value"
+SINGLE_QUOTES='single quoted value'
+MIXED_QUOTES="'mixed' quotes"
+NESTED_QUOTES='"nested" quotes'
+UNBALANCED_QUOTES="unbalanced quotes
+UNBALANCED_QUOTES2=unbalanced quotes"
+QUOTES_IN_MIDDLE=value "with" quotes
+`
+	variables, err := ParseFromReader(strings.NewReader(content), nil)
+	assert.NilError(t, err)
+
+	expectedLines := []string{
+		"DOUBLE_QUOTES=double quoted value",
+		"SINGLE_QUOTES=single quoted value",
+		"MIXED_QUOTES='mixed' quotes",
+		"NESTED_QUOTES=\"nested\" quotes",
+		"UNBALANCED_QUOTES=\"unbalanced quotes",
+		"UNBALANCED_QUOTES2=unbalanced quotes\"",
+		"QUOTES_IN_MIDDLE=value \"with\" quotes",
+	}
+	assert.Check(t, is.DeepEqual(variables, expectedLines))
+}