Move delimiter token skipping to BracketTracker

Also, added lambda argument delimiter skipping.

Fixes #133

diff --git a/README.md b/README.md
index 9522ec5f3acde3ce7d0f2d6f19e38c9190d07436..5be349e42f28bbb5c5799ffd13f95de9bd984a2e 100644 (file)
--- a/README.md
+++ b/README.md
@@ -516,9 +516,11 @@ More details can be found in [CONTRIBUTING](CONTRIBUTING.md).
 * generalized star expression handling, including double stars; this
   fixes multiplication making expressions "unsafe" for trailing commas (#132)
 
-* fix parsing of complex expressions after star and double stars in
+* fixed parsing of complex expressions after star and double stars in
   function parameters (#2)
 
+* fixed invalid splitting on comma in lambda arguments (#133)
+
 ### 18.4a2
 
 * fixed parsing of unaligned standalone comments (#99, #112)

diff --git a/black.py b/black.py
index 9dd3536ab8f0fc3c282310b9b8adeb437a750465..58f7976aa60bc72b0ceb72b5a160a6107bf6637b 100644 (file)
--- a/black.py
+++ b/black.py
@@ -609,6 +609,8 @@ class BracketTracker:
     bracket_match: Dict[Tuple[Depth, NodeType], Leaf] = Factory(dict)
     delimiters: Dict[LeafID, Priority] = Factory(dict)
     previous: Optional[Leaf] = None
+    _for_loop_variable: bool = False
+    _lambda_arguments: bool = False
 
     def mark(self, leaf: Leaf) -> None:
         """Mark `leaf` with bracket-related metadata. Keep track of delimiters.
@@ -628,6 +630,8 @@ class BracketTracker:
         if leaf.type == token.COMMENT:
             return
 
+        self.maybe_decrement_after_for_loop_variable(leaf)
+        self.maybe_decrement_after_lambda_arguments(leaf)
         if leaf.type in CLOSING_BRACKETS:
             self.depth -= 1
             opening_bracket = self.bracket_match.pop((self.depth, leaf.type))
@@ -645,6 +649,8 @@ class BracketTracker:
             self.bracket_match[self.depth, BRACKET[leaf.type]] = leaf
             self.depth += 1
         self.previous = leaf
+        self.maybe_increment_lambda_arguments(leaf)
+        self.maybe_increment_for_loop_variable(leaf)
 
     def any_open_brackets(self) -> bool:
         """Return True if there is an yet unmatched open bracket on the line."""
@@ -658,6 +664,50 @@ class BracketTracker:
         """
         return max(v for k, v in self.delimiters.items() if k not in exclude)
 
+    def maybe_increment_for_loop_variable(self, leaf: Leaf) -> bool:
+        """In a for loop, or comprehension, the variables are often unpacks.
+
+        To avoid splitting on the comma in this situation, increase the depth of
+        tokens between `for` and `in`.
+        """
+        if leaf.type == token.NAME and leaf.value == "for":
+            self.depth += 1
+            self._for_loop_variable = True
+            return True
+
+        return False
+
+    def maybe_decrement_after_for_loop_variable(self, leaf: Leaf) -> bool:
+        """See `maybe_increment_for_loop_variable` above for explanation."""
+        if self._for_loop_variable and leaf.type == token.NAME and leaf.value == "in":
+            self.depth -= 1
+            self._for_loop_variable = False
+            return True
+
+        return False
+
+    def maybe_increment_lambda_arguments(self, leaf: Leaf) -> bool:
+        """In a lambda expression, there might be more than one argument.
+
+        To avoid splitting on the comma in this situation, increase the depth of
+        tokens between `lambda` and `:`.
+        """
+        if leaf.type == token.NAME and leaf.value == "lambda":
+            self.depth += 1
+            self._lambda_arguments = True
+            return True
+
+        return False
+
+    def maybe_decrement_after_lambda_arguments(self, leaf: Leaf) -> bool:
+        """See `maybe_increment_lambda_arguments` above for explanation."""
+        if self._lambda_arguments and leaf.type == token.COLON:
+            self.depth -= 1
+            self._lambda_arguments = False
+            return True
+
+        return False
+
 
 @dataclass
 class Line:
@@ -668,8 +718,6 @@ class Line:
     comments: List[Tuple[Index, Leaf]] = Factory(list)
     bracket_tracker: BracketTracker = Factory(BracketTracker)
     inside_brackets: bool = False
-    has_for: bool = False
-    _for_loop_variable: bool = False
 
     def append(self, leaf: Leaf, preformatted: bool = False) -> None:
         """Add a new `leaf` to the end of the line.
@@ -690,10 +738,8 @@ class Line:
             # imports, for which we only preserve newlines.
             leaf.prefix += whitespace(leaf)
         if self.inside_brackets or not preformatted:
-            self.maybe_decrement_after_for_loop_variable(leaf)
             self.bracket_tracker.mark(leaf)
             self.maybe_remove_trailing_comma(leaf)
-            self.maybe_increment_for_loop_variable(leaf)
 
         if not self.append_comment(leaf):
             self.leaves.append(leaf)
@@ -840,29 +886,6 @@ class Line:
 
         return False
 
-    def maybe_increment_for_loop_variable(self, leaf: Leaf) -> bool:
-        """In a for loop, or comprehension, the variables are often unpacks.
-
-        To avoid splitting on the comma in this situation, increase the depth of
-        tokens between `for` and `in`.
-        """
-        if leaf.type == token.NAME and leaf.value == "for":
-            self.has_for = True
-            self.bracket_tracker.depth += 1
-            self._for_loop_variable = True
-            return True
-
-        return False
-
-    def maybe_decrement_after_for_loop_variable(self, leaf: Leaf) -> bool:
-        """See `maybe_increment_for_loop_variable` above for explanation."""
-        if self._for_loop_variable and leaf.type == token.NAME and leaf.value == "in":
-            self.bracket_tracker.depth -= 1
-            self._for_loop_variable = False
-            return True
-
-        return False
-
     def append_comment(self, comment: Leaf) -> bool:
         """Add an inline or standalone comment to the line."""
         if (

diff --git a/tests/expression.diff b/tests/expression.diff
index dd9459c4453593e8ab186ba2c51c6720740d6888..9da00484c384d101bf8c088378ec8f4883c5572a 100644 (file)
--- a/tests/expression.diff
+++ b/tests/expression.diff
@@ -11,7 +11,7 @@
  True
  False
  1
-@@ -29,59 +29,73 @@
+@@ -29,60 +29,78 @@
  ~great
  +value
  -1
@@ -24,8 +24,14 @@
  lambda a, b, c=True: a
 -lambda a, b, c=True, *, d=(1 << v2), e='str': a
 -lambda a, b, c=True, *vararg, d=(v1 << 2), e='str', **kwargs: a + b
+-foo = (lambda port_id, ignore_missing: {"port1": port1_resource, "port2": port2_resource}[port_id])
 +lambda a, b, c=True, *, d=(1 << v2), e="str": a
 +lambda a, b, c=True, *vararg, d=(v1 << 2), e="str", **kwargs: a + b
++foo = (
++    lambda port_id, ignore_missing: {"port1": port1_resource, "port2": port2_resource}[
++        port_id
++    ]
++)
  1 if True else 2
  str or None if True else str or bytes or None
  (str or None) if True else (str or bytes or None)
@@ -104,7 +110,7 @@
  call(**self.screen_kwargs)
  call(b, **self.screen_kwargs)
  lukasz.langa.pl
-@@ -90,11 +104,11 @@
+@@ -91,11 +109,11 @@
  1.0 .real
  ....__class__
  list[str]
@@ -117,7 +123,7 @@
  ]
  slice[0]
  slice[0:1]
-@@ -121,88 +135,122 @@
+@@ -122,88 +140,122 @@
  numpy[-(c + 1):, d]
  numpy[:, l[-2]]
  numpy[:, ::-1]

diff --git a/tests/expression.py b/tests/expression.py
index 2ecf5223374972a54d3a71bcf754774eb83ec733..c67505fc1fbf3d42370b2ab0b93bccabdbb29743 100644 (file)
--- a/tests/expression.py
+++ b/tests/expression.py
@@ -37,6 +37,7 @@ lambda a=True: a
 lambda a, b, c=True: a
 lambda a, b, c=True, *, d=(1 << v2), e='str': a
 lambda a, b, c=True, *vararg, d=(v1 << 2), e='str', **kwargs: a + b
+foo = (lambda port_id, ignore_missing: {"port1": port1_resource, "port2": port2_resource}[port_id])
 1 if True else 2
 str or None if True else str or bytes or None
 (str or None) if True else (str or bytes or None)
@@ -249,6 +250,11 @@ lambda a=True: a
 lambda a, b, c=True: a
 lambda a, b, c=True, *, d=(1 << v2), e="str": a
 lambda a, b, c=True, *vararg, d=(v1 << 2), e="str", **kwargs: a + b
+foo = (
+    lambda port_id, ignore_missing: {"port1": port1_resource, "port2": port2_resource}[
+        port_id
+    ]
+)
 1 if True else 2
 str or None if True else str or bytes or None
 (str or None) if True else (str or bytes or None)