format: Fix indentation with parentheses

- Split long expressions in () according to max line length
- Partly revert d028502 . Fixes #14935.
- Fixes #15032.

7 files changed, 137 insertions, 40 deletions

diff --git a/mesonbuild/mformat.py b/mesonbuild/mformat.py
index 6b0429b2f..1bf7effd9 100644
--- a/mesonbuild/mformat.py
+++ b/mesonbuild/mformat.py
@@ -255,6 +255,19 @@ class MultilineArgumentDetector(FullAstVisitor):
         super().visit_ArgumentNode(node)
 
 
+class MultilineParenthesesDetector(FullAstVisitor):
+
+    def __init__(self) -> None:
+        self.last_whitespaces: T.Optional[mparser.WhitespaceNode] = None
+
+    def enter_node(self, node: mparser.BaseNode) -> None:
+        self.last_whitespaces = None
+
+    def exit_node(self, node: mparser.BaseNode) -> None:
+        if node.whitespaces and node.whitespaces.value:
+            self.last_whitespaces = node.whitespaces
+
+
 class TrimWhitespaces(FullAstVisitor):
 
     def __init__(self, config: FormatterConfig):
@@ -288,6 +301,8 @@ class TrimWhitespaces(FullAstVisitor):
     def add_space_after(self, node: mparser.BaseNode) -> None:
         if not node.whitespaces.value:
             node.whitespaces.value = ' '
+        elif '#' not in node.whitespaces.value:
+            node.whitespaces.value = ' '
 
     def add_nl_after(self, node: mparser.BaseNode, force: bool = False) -> None:
         if not node.whitespaces.value:
@@ -540,18 +555,28 @@ class TrimWhitespaces(FullAstVisitor):
     def visit_ParenthesizedNode(self, node: mparser.ParenthesizedNode) -> None:
         self.enter_node(node)
 
-        is_multiline = node.lpar.lineno != node.rpar.lineno
-        if is_multiline:
+        if node.lpar.whitespaces and '#' in node.lpar.whitespaces.value:
+            node.is_multiline = True
+
+        elif not node.is_multiline:
+            ml_detector = MultilineParenthesesDetector()
+            node.inner.accept(ml_detector)
+            if ml_detector.last_whitespaces and '\n' in ml_detector.last_whitespaces.value:
+                # We keep it multiline if last parenthesis is on a separate line
+                node.is_multiline = True
+
+        if node.is_multiline:
             self.indent_comments += self.config.indent_by
 
         node.lpar.accept(self)
         node.inner.accept(self)
 
-        if is_multiline:
+        if node.is_multiline:
             node.inner.whitespaces.value = self.dedent(node.inner.whitespaces.value)
             self.indent_comments = self.dedent(self.indent_comments)
-            if node.lpar.whitespaces and '\n' in node.lpar.whitespaces.value:
-                self.add_nl_after(node.inner)
+            self.add_nl_after(node.inner)
+        else:
+            node.inner.whitespaces = None
 
         node.rpar.accept(self)
         self.move_whitespaces(node.rpar, node)
@@ -564,6 +589,7 @@ class ArgumentFormatter(FullAstVisitor):
         self.level = 0
         self.indent_after = False
         self.is_function_arguments = False
+        self.par_level = 0
 
     def add_space_after(self, node: mparser.BaseNode) -> None:
         if not node.whitespaces.value:
@@ -573,7 +599,7 @@ class ArgumentFormatter(FullAstVisitor):
         if not node.whitespaces.value or node.whitespaces.value == ' ':
             node.whitespaces.value = '\n'
         indent_by = (node.condition_level + indent) * self.config.indent_by
-        if indent_by:
+        if indent_by and node.whitespaces.value.endswith('\n'):
             node.whitespaces.value += indent_by
 
     def visit_ArrayNode(self, node: mparser.ArrayNode) -> None:
@@ -682,11 +708,11 @@ class ArgumentFormatter(FullAstVisitor):
                         # keep '--arg', 'value' on same line
                         self.add_space_after(node.commas[arg_index])
                     elif arg_index < len(node.commas):
-                        self.add_nl_after(node.commas[arg_index], self.level)
+                        self.add_nl_after(node.commas[arg_index], self.level + self.par_level)
                     arg_index += 1
 
             for comma in node.commas[arg_index:-1]:
-                self.add_nl_after(comma, self.level)
+                self.add_nl_after(comma, self.level + self.par_level)
             if node.arguments or node.kwargs:
                 self.add_nl_after(node, self.level - 1)
 
@@ -701,17 +727,38 @@ class ArgumentFormatter(FullAstVisitor):
 
     def visit_ParenthesizedNode(self, node: mparser.ParenthesizedNode) -> None:
         self.enter_node(node)
-        is_multiline = '\n' in node.lpar.whitespaces.value
-        if is_multiline:
+        if node.is_multiline:
+            self.par_level += 1
             current_indent_after = self.indent_after
             self.indent_after = True
         node.lpar.accept(self)
+        if node.is_multiline:
+            self.add_nl_after(node.lpar, indent=self.level + self.par_level)
         node.inner.accept(self)
-        if is_multiline:
+        if node.is_multiline:
+            self.par_level -= 1
             self.indent_after = current_indent_after
         node.rpar.accept(self)
         self.exit_node(node)
 
+    def visit_OrNode(self, node: mparser.OrNode) -> None:
+        self.enter_node(node)
+        node.left.accept(self)
+        if self.par_level:
+            self.add_nl_after(node.left, indent=self.level + self.par_level)
+        node.operator.accept(self)
+        node.right.accept(self)
+        self.exit_node(node)
+
+    def visit_AndNode(self, node: mparser.AndNode) -> None:
+        self.enter_node(node)
+        node.left.accept(self)
+        if self.par_level:
+            self.add_nl_after(node.left, indent=self.level + self.par_level)
+        node.operator.accept(self)
+        node.right.accept(self)
+        self.exit_node(node)
+
 
 class ComputeLineLengths(FullAstVisitor):
 
@@ -811,6 +858,16 @@ class ComputeLineLengths(FullAstVisitor):
         self.split_if_needed(node.args)  # split if closing bracket is too far
         self.exit_node(node)
 
+    def visit_ParenthesizedNode(self, node: mparser.ParenthesizedNode) -> None:
+        self.enter_node(node)
+        node.lpar.accept(self)
+        node.inner.accept(self)
+        node.rpar.accept(self)
+        if not node.is_multiline and self.length > self.config.max_line_length:
+            node.is_multiline = True
+            self.need_regenerate = True
+        self.exit_node(node)
+
 
 class SubdirFetcher(FullAstVisitor):
 
diff --git a/mesonbuild/mparser.py b/mesonbuild/mparser.py
index 3dd8f0a5e..a42fcdb06 100644
--- a/mesonbuild/mparser.py
+++ b/mesonbuild/mparser.py
@@ -656,13 +656,14 @@ class ParenthesizedNode(BaseNode):
     lpar: SymbolNode = field(hash=False)
     inner: BaseNode
     rpar: SymbolNode = field(hash=False)
+    is_multiline: bool
 
     def __init__(self, lpar: SymbolNode, inner: BaseNode, rpar: SymbolNode):
         super().__init__(lpar.lineno, lpar.colno, inner.filename, end_lineno=rpar.lineno, end_colno=rpar.colno+1)
         self.lpar = lpar
         self.inner = inner
         self.rpar = rpar
-
+        self.is_multiline = False
 
 if T.TYPE_CHECKING:
     COMPARISONS = Literal['==', '!=', '<', '<=', '>=', '>', 'in', 'notin']
diff --git a/test cases/format/1 default/indentation.meson b/test cases/format/1 default/indentation.meson
index f18b23072..7b26e49b1 100644
--- a/test cases/format/1 default/indentation.meson
+++ b/test cases/format/1 default/indentation.meson
@@ -100,3 +100,13 @@ n = [
     2,
     3,
 ]
+
+# Overindent regressions (issue #14935)
+if (host_cpu_family == 'x86' and host_system in [
+    'cygwin',
+    'windows',
+    'os2',
+    'interix',
+])
+    message('hi')
+endif
diff --git a/test cases/format/5 transform/default.expected.meson b/test cases/format/5 transform/default.expected.meson
index 4a9851ac9..702ae5643 100644
--- a/test cases/format/5 transform/default.expected.meson
+++ b/test cases/format/5 transform/default.expected.meson
@@ -8,7 +8,7 @@ f = files(options_ini, 'expected.meson', 'source.meson')
 # This array should fit on one line
 a1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21]
 
-# This array is too long and should be splitted
+# This array is too long and should be split
 a2 = [
     2,
     3,
@@ -81,4 +81,17 @@ arguments = [
     '--x',
 ]
 
+# issue #15032
+if true
+    if true
+        if (
+            true
+            and true
+            and false
+        )
+            message('Hello, world!')
+        endif
+    endif
+endif
+
 # no final endline
diff --git a/test cases/format/5 transform/muon.expected.meson b/test cases/format/5 transform/muon.expected.meson
index 3b6127030..f01849734 100644
--- a/test cases/format/5 transform/muon.expected.meson
+++ b/test cases/format/5 transform/muon.expected.meson
@@ -8,7 +8,7 @@ f = files('expected.meson', 'source.meson', options_ini)
 # This array should fit on one line
 a1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21]
 
-# This array is too long and should be splitted
+# This array is too long and should be split
 a2 = [
     2,
     3,
@@ -81,4 +81,17 @@ arguments = [
     '--x',
 ]
 
+# issue #15032
+if true
+    if true
+        if (
+            true
+            and true
+            and false
+        )
+            message('Hello, world!')
+        endif
+    endif
+endif
+
 # no final endline
diff --git a/test cases/format/5 transform/options.expected.meson b/test cases/format/5 transform/options.expected.meson
index 84917c19d..7136506c0 100644
--- a/test cases/format/5 transform/options.expected.meson
+++ b/test cases/format/5 transform/options.expected.meson
@@ -8,25 +8,14 @@ f = files(options_ini, 'expected.meson', 'source.meson')
 # This array should fit on one line
 a1 = [ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21 ]
 
-# This array is too long and should be splitted
+# This array is too long and should be split
 a2 = [ 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 ]
 
 # space array
 a3 = [ 1, 2, 3 ]
 
 # multi line expression
-is_foo = (
-  true
-  and false
-  and true
-  and false
-  and true
-  and false
-  and true
-  and false
-  and true
-  and false
-)
+is_foo = (true and false and true and false and true and false and true and false and true and false)
 
 # no single comma function
 fct = files(
@@ -60,4 +49,17 @@ arguments = [
   '--x',
 ]
 
+# issue #15032
+if true
+  if true
+    if (
+      true
+      and true
+      and false
+    )
+      message('Hello, world!')
+    endif
+  endif
+endif
+
 # no final endline
\ No newline at end of file
diff --git a/test cases/format/5 transform/source.meson b/test cases/format/5 transform/source.meson
index a3b326b12..554b9e6a7 100644
--- a/test cases/format/5 transform/source.meson
+++ b/test cases/format/5 transform/source.meson
@@ -12,25 +12,14 @@ f = files(
 # This array should fit on one line
 a1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21]
 
-# This array is too long and should be splitted
+# This array is too long and should be split
 a2 = [2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22]
 
 # space array
 a3 = [ 1, 2, 3 ]
 
 # multi line expression
-is_foo = (
-    true
-    and false
-    and true
-    and false
-    and true
-    and false
-    and true
-    and false
-    and true
-    and false
-)
+is_foo = (true and false and true and false and true and false and true and false and true and false)
 
 # no single comma function
 fct = files(
@@ -49,4 +38,16 @@ f'This is not a fstring'
 arguments = ['a', '--opt_a', 'opt_a_value', 'b', 'c', '--opt_d', '--opt_e', 'opt_e_value',
 '--opt_f', '--opt_g', 'opt_g_value', 'other_value', 'again', '--x']
 
+# issue #15032
+if true
+    if true
+        if (true and
+            true and
+            false
+        )
+            message('Hello, world!')
+        endif
+    endif
+endif
+
 # no final endline
\ No newline at end of file