[Python] Fix broken highlighting after case statements (#4436)

* [Python] Fix function definitions in first case branch

This commit removes `^\s*` restriction from function definitions' patterns
to ensure those are matched after first case statements.

Leading whitespace of a line after first case statement is already consumed
and scoped `meta.disable-dedentation` to support ST's indentation engine.

For consistency the restriction is globally removed, so space before `def`
keyword is never scoped `meta.function`.

* [Python] Fix class definitions in first case branch

This commit removes `^\s*` restriction from class definitions' patterns
to ensure those are matched after first case statements.

Leading whitespace of a line after first case statement is already consumed
and scoped `meta.disable-dedentation` to support ST's indentation engine.

For consistency the restriction is globally removed, so space before `class`
keyword is never scoped `meta.class`.

* [Python] Fix type definitions in first case branch

This commit removes `^\s*` restriction from type definitions' patterns
to ensure those are matched after first case statements.

Leading whitespace of a line after first case statement is already consumed
and scoped `meta.disable-dedentation` to support ST's indentation engine.

For consistency the restriction is globally removed, so space before `type`
keyword is never scoped `meta.type-alias`.

* [Python] Fix decorators in first case branch

This commit pushes a special context for special patterns right after first
case statement in order to consume decorators.

A `@` denotes an decorator only at the beginning of a line.
In any other position it is an operator.

* [Python] Verify conflict markers after case statements

Author: deathaxe

Python/Python.sublime-syntax

@@ -789,10 +789,8 @@ contexts:
 ###[ CLASS DEFINITIONS ]######################################################
 
   class-definitions:
-    - match: ^\s*(class)\b
-      scope: meta.class.python
-      captures:
-        1: keyword.declaration.class.python
+    - match: class\b
+      scope: meta.class.python keyword.declaration.class.python
       push:
         - class-definition-base-list
         - type-parameter-list
@@ -860,7 +858,7 @@ contexts:
 ###[ FUNCTION DEFINITIONS ]###################################################
 
   function-definitions:
-    - match: ^\s*(?:(async)\s+)?(def)\b
+    - match: (?:(async)\s+)?(def)\b
       scope: meta.function.python
       captures:
         1: keyword.declaration.async.python
@@ -1074,17 +1072,16 @@ contexts:
 ###[ TYPE DEFINITIONS ]#######################################################
 
   type-definitions:
-    - match: ^(?=\s*type\b)
+    - match: (?=type\b)
       branch_point: type-definitions
       branch:
         - type-definition
         - type-definition-fallback
 
   type-definition:
     - meta_include_prototype: false
-    - match: \s*(type)\b
-      captures:
-        1: keyword.declaration.class.python
+    - match: type\b
+      scope: keyword.declaration.class.python
       set:
         - type-definition-meta
         - type-definition-value-assignment
@@ -1621,12 +1618,20 @@ contexts:
         meta.statement.conditional.case.python
         keyword.control.conditional.case.python
       set:
+        - after-first-case-statement
         - meta-disable-dedentation
         - case-statement-pattern
         - allow-unpack-operators
     - include: comments
     - include: else-pop
 
+  after-first-case-statement:
+    - meta_include_prototype: false
+    - match: \@
+      scope: meta.annotation.python punctuation.definition.annotation.python
+      set: decorator-body
+    - include: immediately-pop
+
   meta-disable-dedentation:
     - meta_include_prototype: false
     - meta_scope: meta.disable-dedentation.python

Python/tests/syntax_test_conflicts.py

@@ -721,3 +721,43 @@
 #       ^^^^^^ meta.block.conflict.end.diff entity.name.section.diff
 #             ^ meta.block.conflict.end.diff - entity - punctuation
 '''
+
+match test:
+    case "before":
+<<<<<<< HEAD
+# <- meta.block.conflict.begin.diff punctuation.section.block.begin.diff
+# ^^^^^ meta.block.conflict.begin.diff punctuation.section.block.begin.diff
+#      ^ meta.block.conflict.begin.diff - entity - punctuation
+#       ^^^^ meta.block.conflict.begin.diff entity.name.section.diff
+#           ^ meta.block.conflict.begin.diff - entity - punctuation
+    case "ours":
+#   ^^^^ meta.statement.conditional.case.python keyword.control.conditional.case.python
+#       ^^^^^^^ meta.statement.conditional.case.patterns.python
+#        ^^^^^^ meta.string.python string.quoted.double.python
+#        ^ punctuation.definition.string.begin.python
+#             ^ punctuation.definition.string.end.python
+#              ^ meta.statement.conditional.case.python punctuation.section.block.begin.python
+=======
+# <- meta.block.conflict.separator.diff punctuation.section.block.diff
+# ^^^^^ meta.block.conflict.separator.diff punctuation.section.block.diff
+#      ^ meta.block.conflict.separator.diff - punctuation
+    case "theirs":
+#   ^^^^ meta.statement.conditional.case.python keyword.control.conditional.case.python
+#       ^^^^^^^^^ meta.statement.conditional.case.patterns.python
+#        ^^^^^^^^ meta.string.python string.quoted.double.python
+#        ^ punctuation.definition.string.begin.python
+#               ^ punctuation.definition.string.end.python
+#                ^ meta.statement.conditional.case.python punctuation.section.block.begin.python
+>>>>>>> master
+# <- meta.block.conflict.end.diff punctuation.section.block.end.diff
+# ^^^^^ meta.block.conflict.end.diff punctuation.section.block.end.diff
+#      ^ meta.block.conflict.end.diff - entity - punctuation
+#       ^^^^^^ meta.block.conflict.end.diff entity.name.section.diff
+#             ^ meta.block.conflict.end.diff - entity - punctuation
+    case "after":
+#   ^^^^ meta.statement.conditional.case.python keyword.control.conditional.case.python
+#       ^^^^^^^^ meta.statement.conditional.case.patterns.python
+#        ^^^^^^^ meta.string.python string.quoted.double.python
+#        ^ punctuation.definition.string.begin.python
+#              ^ punctuation.definition.string.end.python
+#               ^ meta.statement.conditional.case.python punctuation.section.block.begin.python

Python/tests/syntax_test_python.py

@@ -2146,6 +2146,20 @@ def f[
 #          ^ meta.type.python meta.path.python meta.generic-name.python
 #           ^ meta.function.python punctuation.section.block.begin.python
 
+match test:
+    case "func":
+        def func(arg): pass
+# <- meta.disable-dedentation.python - meta.function
+#^^^^^^^ meta.disable-dedentation.python - meta.function
+#       ^^^^^^^^ meta.function.python
+#       ^^^ keyword.declaration.function.python
+#           ^^^^ entity.name.function.python
+#               ^^^^^ meta.function.parameters.python
+#               ^ punctuation.section.parameters.begin.python
+#                ^^^ variable.parameter.python
+#                   ^ punctuation.section.parameters.end.python
+#                    ^ meta.function.python punctuation.section.block.begin.python
+#                      ^^^^ keyword.control.flow.pass.python
 
 ##################
 # Class definitions
@@ -2310,6 +2324,19 @@ def method(arg: T):
 #             ^^^^^^^^ meta.function.parameters
 #                   ^ meta.type.python meta.path.python meta.generic-name.python
 
+match test:
+    case "class":
+        class name(): pass
+# <- meta.disable-dedentation.python - meta.class
+#^^^^^^^ meta.disable-dedentation.python - meta.class
+#       ^^^^^^^^^^ meta.class.python
+#       ^^^^^ keyword.declaration.class.python
+#             ^^^^ entity.name.class.python
+#                 ^^ meta.class.inheritance.python
+#                 ^ punctuation.section.inheritance.begin.python
+#                  ^ punctuation.section.inheritance.end.python
+#                   ^ meta.class.python punctuation.section.block.begin.python
+#                     ^^^^ keyword.control.flow.pass.python
 
 ##################
 # Type definitions
@@ -2389,8 +2416,9 @@ def method(arg: T):
 #        ^ punctuation.section.brackets.end.python
 
   type Alias
-# <- meta.type-alias.python
-#^^^^^^^^^^^ meta.type-alias.python
+# <- - meta.type-alias
+#^ - meta.type-alias
+# ^^^^^^^^^^ meta.type-alias.python
 # ^^^^ keyword.declaration.class.python
 #      ^^^^^ entity.name.type.alias.python
 
@@ -2429,7 +2457,7 @@ def __init__(self, type: int):
 #                      ^^^^ variable.parameter.python
         self.type = type
 #            ^^^^ meta.path.python meta.generic-name.python
-#                   ^^^^ meta.path.python meta.generic-name.python
+#                   ^^^^ meta.generic-name.python
 
         self.me = type(type)
 #                 ^^^^ meta.function-call.identifier.python support.function.builtin.python
@@ -2438,6 +2466,14 @@ def __init__(self, type: int):
 #                      ^^^^ meta.path.python meta.generic-name.python
 #                          ^ punctuation.section.arguments.end.python
 
+match test:
+    case "type":
+        type foo
+#^^^^^^^ meta.disable-dedentation.python - meta.type
+#       ^^^^^^^^ meta.type-alias.python
+#       ^^^^ keyword.declaration.class.python
+#            ^^^ entity.name.type.alias.python
+
 ##################
 # Decorators
 ##################
@@ -2592,6 +2628,14 @@ def f(): pass
 #                           ^^^^^^^ variable.annotation.python
 #
 
+match test:
+    case "func":
+        @guarded
+#^^^^^^^ meta.disable-dedentation.python - meta.annotation
+#       ^^^^^^^^ meta.annotation.python
+#       ^ punctuation.definition.annotation.python
+#        ^^^^^^^ variable.annotation.python
+
 ##################
 # Collection literals and generators
 ##################
@@ -3087,8 +3131,11 @@ class Cls:
     __slots__ = "item",
 
     def method():
-# <- meta.function.python
-#^^^^^^^^^^^^^^^^ meta.function
+# <- - meta.function
+#^^^ - meta.function
+#   ^^^^^^^^^^ meta.function.python
+#             ^^ meta.function.parameters.python
+#               ^ meta.function.python
 #   ^^^ keyword.declaration.function.python
 #       ^^^^^^ entity.name.function.python
 #             ^ punctuation.section.parameters.begin.python