[Compiler] format generated code by header and line break #3233

Author: Lavisha Gupta

compiler/fory_compiler/generators/base.py

@@ -206,3 +206,121 @@ def get_license_header(self, comment_prefix: str = "//") -> str:
         return "\n".join(
             f"{comment_prefix} {line}" if line else comment_prefix for line in lines
         )
+
+    def wrap_line(
+        self,
+        line: str,
+        max_width: int = 80,
+        indent: str = "",
+        continuation_indent: str = None,
+    ) -> List[str]:
+        """Wrap a long line into multiple lines with max_width characters.
+
+        Args:
+            line: The line to wrap
+            max_width: Maximum width per line (default 80)
+            indent: The indentation to preserve for the first line
+            continuation_indent: Extra indentation for continuation lines.
+                                If None, uses indent + 4 spaces.
+
+        Returns:
+            List of wrapped lines
+        """
+        if continuation_indent is None:
+            continuation_indent = indent + "    "
+
+        # If line is already short enough, return as is
+        if len(line) <= max_width:
+            return [line]
+
+        # Don't wrap C++ preprocessor directives (macros)
+        stripped = line.lstrip()
+        if stripped.startswith("#"):
+            return [line]
+
+        # Don't wrap comment lines (license headers, etc.)
+        if stripped.startswith("//") or stripped.startswith("/*") or stripped.startswith("*") or stripped.startswith("#"):
+            return [line]
+
+        # Extract the leading indent
+        leading_spaces = line[: len(line) - len(line.lstrip())]
+
+        # Get the content without indent
+        content = line[len(leading_spaces) :]
+
+        # If it's still too short after considering indent, don't wrap
+        if len(leading_spaces) + len(content) <= max_width:
+            return [line]
+
+        # Find good break points (prefer breaking at spaces, commas, operators)
+        result = []
+        current = content
+        first_line = True
+
+        while len(leading_spaces) + len(current) > max_width:
+            # Calculate available width
+            if first_line:
+                available = max_width - len(leading_spaces)
+            else:
+                available = max_width - len(continuation_indent)
+
+            if available <= 0:
+                # Can't wrap reasonably, return original
+                return [line]
+
+            # Find the best break point
+            break_point = -1
+
+            # Look for break points in order of preference
+            search_text = current[:available]
+
+            # Try to break at common delimiters (working backwards)
+            for delimiter in [", ", " && ", " || ", " + ", " - ", " * ", " / ", " = ", " ", ","]:
+                idx = search_text.rfind(delimiter)
+                if idx > 0:
+                    break_point = idx + len(delimiter)
+                    break
+
+            # If no good break point found, just break at max width
+            if break_point <= 0:
+                break_point = available
+
+            # Add the line segment
+            if first_line:
+                result.append(leading_spaces + current[:break_point].rstrip())
+                first_line = False
+            else:
+                result.append(continuation_indent + current[:break_point].rstrip())
+
+            # Continue with the rest
+            current = current[break_point:].lstrip()
+
+        # Add the remaining content
+        if current:
+            if first_line:
+                result.append(leading_spaces + current)
+            else:
+                result.append(continuation_indent + current)
+
+        return result if result else [line]
+
+    def wrap_lines(
+        self, lines: List[str], max_width: int = 80, preserve_blank: bool = True
+    ) -> List[str]:
+        """Wrap multiple lines, handling each line's indentation.
+
+        Args:
+            lines: List of lines to wrap
+            max_width: Maximum width per line
+            preserve_blank: If True, preserve blank lines as-is
+
+        Returns:
+            List of wrapped lines
+        """
+        result = []
+        for line in lines:
+            if preserve_blank and not line.strip():
+                result.append(line)
+            else:
+                result.extend(self.wrap_line(line, max_width))
+        return result

compiler/fory_compiler/generators/cpp.py

@@ -370,9 +370,12 @@ def generate_header(self) -> GeneratedFile:
         lines.append(f"#endif // {guard_name}")
         lines.append("")
 
+        # Wrap long lines at 80 characters (careful with C++ macros)
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+
         return GeneratedFile(
             path=f"{self.get_header_name()}.h",
-            content="\n".join(lines),
+            content="\n".join(wrapped_lines),
         )
 
     def collect_message_includes(self, message: Message, includes: Set[str]):

compiler/fory_compiler/generators/go.py

@@ -449,9 +449,12 @@ def generate_file(self) -> GeneratedFile:
         lines.extend(self.generate_fory_helpers())
         lines.append("")
 
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+
         return GeneratedFile(
             path=f"{self.get_file_name()}.go",
-            content="\n".join(lines),
+            content="\n".join(wrapped_lines),
         )
 
     def collect_message_imports(self, message: Message, imports: Set[str]):

compiler/fory_compiler/generators/java.py

@@ -366,7 +366,9 @@ def generate_enum_file(self, enum: Enum) -> GeneratedFile:
         else:
             path = f"{enum.name}.java"
 
-        return GeneratedFile(path=path, content="\n".join(lines))
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+        return GeneratedFile(path=path, content="\n".join(wrapped_lines))
 
     def generate_union_file(self, union: Union) -> GeneratedFile:
         """Generate a Java union class file."""
@@ -397,7 +399,9 @@ def generate_union_file(self, union: Union) -> GeneratedFile:
         else:
             path = f"{union.name}.java"
 
-        return GeneratedFile(path=path, content="\n".join(lines))
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+        return GeneratedFile(path=path, content="\n".join(wrapped_lines))
 
     def generate_message_file(self, message: Message) -> GeneratedFile:
         """Generate a Java class file for a message."""
@@ -486,7 +490,9 @@ def generate_message_file(self, message: Message) -> GeneratedFile:
         else:
             path = f"{message.name}.java"
 
-        return GeneratedFile(path=path, content="\n".join(lines))
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+        return GeneratedFile(path=path, content="\n".join(wrapped_lines))
 
     def generate_outer_class_file(self, outer_classname: str) -> GeneratedFile:
         """Generate a single Java file with all types as inner classes of an outer class.
@@ -559,7 +565,9 @@ def generate_outer_class_file(self, outer_classname: str) -> GeneratedFile:
         else:
             path = f"{outer_classname}.java"
 
-        return GeneratedFile(path=path, content="\n".join(lines))
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+        return GeneratedFile(path=path, content="\n".join(wrapped_lines))
 
     def collect_message_imports(self, message: Message, imports: Set[str]):
         """Collect imports for a message and all its nested types recursively."""
@@ -1447,7 +1455,9 @@ def generate_registration_file(
         else:
             path = f"{class_name}.java"
 
-        return GeneratedFile(path=path, content="\n".join(lines))
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+        return GeneratedFile(path=path, content="\n".join(wrapped_lines))
 
     def generate_enum_registration(
         self, lines: List[str], enum: Enum, parent_path: str

compiler/fory_compiler/generators/python.py

@@ -323,9 +323,12 @@ def generate_module(self) -> GeneratedFile:
         lines.extend(self.generate_fory_helpers())
         lines.append("")
 
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+
         return GeneratedFile(
             path=f"{self.get_module_name()}.py",
-            content="\n".join(lines),
+            content="\n".join(wrapped_lines),
         )
 
     def collect_message_imports(self, message: Message, imports: Set[str]):

compiler/fory_compiler/generators/rust.py

@@ -252,9 +252,12 @@ def generate_module(self) -> GeneratedFile:
         lines.extend(self.generate_fory_helpers())
         lines.append("")
 
+        # Wrap long lines at 80 characters
+        wrapped_lines = self.wrap_lines(lines, max_width=80)
+
         return GeneratedFile(
             path=f"{self.get_module_name()}.rs",
-            content="\n".join(lines),
+            content="\n".join(wrapped_lines),
         )
 
     def collect_message_uses(self, message: Message, uses: Set[str]):