Improved parentheses formatting

src/tctools/format.py

@@ -15,6 +15,7 @@
  FormatInsertFinalNewline,
  FormatEndOfLine,
  FormatVariablesAlign,
+ FormatConditionalParentheses,
 )
 
 
@@ -46,6 +47,7 @@ def main(*args) -> int:
  Formatter.register_rule(FormatInsertFinalNewline)
  Formatter.register_rule(FormatEndOfLine)
  Formatter.register_rule(FormatVariablesAlign)
+ Formatter.register_rule(FormatConditionalParentheses)
 
  formatter = Formatter(
  quiet=arguments.quiet,

src/tctools/format_rules.py

@@ -340,22 +340,24 @@ def __init__(self, *args):
 
  self._re_needs_parentheses = re.compile(
  r"""
- ^ # Look for start of string or new line
- (\s*IF\s+) # Match IF with surrounding ws
- ([^(\r\n].+?[^)\r\n]) # Match any characters NOT whitin ()
- (\s+THEN) # Match THEN with preceding ws
+ ^ # Look for start of string or new line
+ \s*IF\s+ # Match IF with surrounding ws
+ ([^(\r\n].+?) # Match any characters NOT starting with (
+ # We cannot match the closing bracket, as this could be
+ # from a function call
+ \s+THEN # Match THEN with preceding ws
  """,
- re.VERBOSE | re.MULTILINE
+ re.VERBOSE | re.MULTILINE,
  )
 
  self._re_removes_parentheses = re.compile(
  r"""
  ^ # Look for start of string or new line
- (\s*IF\s+) # Match IF with surrounding ws
+ \s*IF\s*  # Match IF with surrounding ws
  \((.+)\) # Match any characters whitin ()
- (\s+THEN) # Match THEN with preceding ws
+ \s*THEN  # Match THEN with preceding ws
  """,
- re.VERBOSE | re.MULTILINE
+ re.VERBOSE | re.MULTILINE,
  )
 
  def format(self, content: List[str], kind: Optional[Kind] = None):
@@ -364,12 +366,27 @@ def format(self, content: List[str], kind: Optional[Kind] = None):
 
  if self._parentheses:
  pattern = self._re_needs_parentheses
- replace = r"\1(\2)\3"
  else:
  pattern = self._re_removes_parentheses
- replace = r"\1\2\3"
 
  for i, line in enumerate(content):
- line_new, replacements = pattern.subn(replace, line)
- if replacements > 0:
- content[i] = line_new
+ # Do a manual match + replace, instead of e.g. subn(), because we might
+ # need to add extra spaces after removing parentheses
+ if match := pattern.search(line):
+ prefix = line[: match.start(1)]
+ condition = match.group(1)
+ suffix = line[match.end(1) :]
+
+ if self._parentheses:
+ condition = "(" + condition + ")"
+ else:
+ prefix = prefix[:-1] # Remove parentheses
+ suffix = suffix[1:]
+
+ # Removing the () could cause a syntax error:
+ if not prefix.endswith(" "):
+ prefix += " "
+ if not suffix.startswith(" "):
+ suffix = " " + suffix
+
+ content[i] = prefix + condition + suffix

tests/test_formatting_rules.py

@@ -110,9 +110,9 @@ def test_final_newline(content, expected):
  properties = {"insert_final_newline": True}
 
  rule = format_rules.FormatInsertFinalNewline(properties)
- rule.format(content)
-
- assert content == expected
+ content_new = content.copy()
+ rule.format(content_new)
+ assert content_new == expected
 
 
 content_eol = [
@@ -170,9 +170,9 @@ def test_end_of_line(eol, expected):
 
  content = content_before.copy()
  rule = format_rules.FormatEndOfLine({"end_of_line": eol})
- rule.format(content)
-
- assert content == expected
+ content_new = content.copy()
+ rule.format(content_new)
+ assert content_new == expected
 
 
 content_variables = [
@@ -245,8 +245,9 @@ def test_end_of_line(eol, expected):
 @pytest.mark.parametrize("content,expected,settings", content_variables)
 def test_variable_align(content, expected, settings):
  rule = format_rules.FormatVariablesAlign(settings)
- rule.format(content, Kind.DECLARATION)
- assert content == expected
+ content_new = content.copy()
+ rule.format(content_new, Kind.DECLARATION)
+ assert content_new == expected
 
 
 content_parentheses = [
@@ -272,31 +273,45 @@ def test_variable_align(content, expected, settings):
  ),
  (
  [
- "IF inputs.button = 1 THEN\r\n",
+ "IF func(arg1 := 1, args2 := func2()) THEN\n",
  ],
  [
- "IF(inputs.button = 1)THEN\r\n",
+ "IF (func(arg1 := 1, args2 := func2())) THEN\n",
  ],
  ),
+ # ( # This case fails, because we cannot identify matching parentheses:
+ # [
+ # "IF (1+1)*2 = 3*(x-1) THEN\n",
+ # ],
+ # [
+ # "IF ((1+1)*2 = 3*(x-1)) THEN\n",
+ # ],
+ # ),
 ]
 
 
 @pytest.mark.parametrize("content,expected", content_parentheses)
 def test_parentheses_add(content, expected):
  rule = format_rules.FormatConditionalParentheses({"parentheses_conditionals": True})
- rule.format(content)
- assert content == expected
+ content_new = content.copy()
+ rule.format(content_new)
+ assert content_new == expected
 
 
 @pytest.mark.parametrize("expected,content", content_parentheses)
 def test_parentheses_remove(expected, content):
- rule = format_rules.FormatConditionalParentheses({"parentheses_conditionals": False})
- rule.format(content)
- assert content == expected
+ rule = format_rules.FormatConditionalParentheses(
+ {"parentheses_conditionals": False}
+ )
+ content_new = content.copy()
+ rule.format(content_new)
+ assert content_new == expected
 
 
 def test_parentheses_remove_no_ws():
- rule = format_rules.FormatConditionalParentheses({"parentheses_conditionals": False})
+ rule = format_rules.FormatConditionalParentheses(
+ {"parentheses_conditionals": False}
+ )
  content = ["IF(inputs.button = 1)THEN"]
  rule.format(content)
  assert content == ["IF inputs.button = 1 THEN"]