decompiler: Add more decompilable tags

Add more tags to the list of things the decompiler can handle. This
required some changes to track the containing object class in the
DecompileCtx, since some objects use the same tag names.

The improved support means we can test the decompiler on most of the
test suite. Any new test samples will by default be tested to ensure the
decompiler produces the original blueprint file.

Also, updated the decompiler to always use double quotes.

blueprintcompiler/decompiler.py

@@ -17,8 +17,8 @@
 #
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
-import re
 import typing as T
+from collections import defaultdict
 from dataclasses import dataclass
 from enum import Enum
 
@@ -30,7 +30,7 @@ from .xml_reader import Element, parse, parse_string
 __all__ = ["decompile"]
 
 
-_DECOMPILERS: T.Dict = {}
+_DECOMPILERS: dict[str, list] = defaultdict(list)
 _CLOSING = {
     "{": "}",
     "[": "]",
@@ -54,24 +54,25 @@ class DecompileCtx:
     def __init__(self) -> None:
         self._result: str = ""
         self.gir = GirContext()
-        self._indent: int = 0
         self._blocks_need_end: T.List[str] = []
         self._last_line_type: LineType = LineType.NONE
         self.template_class: T.Optional[str] = None
+        self._obj_type_stack: list[T.Optional[GirType]] = []
+        self._node_stack: list[Element] = []
 
         self.gir.add_namespace(get_namespace("Gtk", "4.0"))
 
     @property
     def result(self) -> str:
-        imports = "\n".join(
+        import_lines = sorted(
             [
                 f"using {ns} {namespace.version};"
                 for ns, namespace in self.gir.namespaces.items()
+                if ns != "Gtk"
             ]
         )
-        full_string = imports + "\n" + self._result
-        formatted_string = formatter.format(full_string)
-        return formatted_string
+        full_string = "\n".join(["using Gtk 4.0;", *import_lines]) + self._result
+        return formatter.format(full_string)
 
     def type_by_cname(self, cname: str) -> T.Optional[GirType]:
         if type := self.gir.get_type_by_cname(cname):
@@ -90,10 +91,26 @@ class DecompileCtx:
 
     def start_block(self) -> None:
         self._blocks_need_end.append("")
+        self._obj_type_stack.append(None)
 
     def end_block(self) -> None:
         if close := self._blocks_need_end.pop():
             self.print(close)
+        self._obj_type_stack.pop()
+
+    @property
+    def current_obj_type(self) -> T.Optional[GirType]:
+        return next((x for x in reversed(self._obj_type_stack) if x is not None), None)
+
+    def push_obj_type(self, type: T.Optional[GirType]) -> None:
+        self._obj_type_stack[-1] = type
+
+    @property
+    def current_node(self) -> T.Optional[Element]:
+        if len(self._node_stack) == 0:
+            return None
+        else:
+            return self._node_stack[-1]
 
     def end_block_with(self, text: str) -> None:
         self._blocks_need_end[-1] = text
@@ -105,7 +122,7 @@ class DecompileCtx:
             if len(self._blocks_need_end):
                 self._blocks_need_end[-1] = _CLOSING[line[-1]]
 
-    def print_attribute(self, name: str, value: str, type: GirType) -> None:
+    def print_value(self, value: str, type: T.Optional[GirType]) -> None:
         def get_enum_name(value):
             for member in type.members.values():
                 if (
@@ -117,12 +134,14 @@ class DecompileCtx:
             return value.replace("-", "_")
 
         if type is None:
-            self.print(f"{name}: {escape_quote(value)};")
+            self.print(f"{escape_quote(value)}")
         elif type.assignable_to(FloatType()):
-            self.print(f"{name}: {value};")
+            self.print(str(value))
         elif type.assignable_to(BoolType()):
             val = truthy(value)
-            self.print(f"{name}: {'true' if val else 'false'};")
+            self.print("true" if val else "false")
+        elif type.assignable_to(ArrayType(StringType())):
+            self.print(f"[{', '.join([escape_quote(x) for x in value.split('\n')])}]")
         elif (
             type.assignable_to(self.gir.namespaces["Gtk"].lookup_type("Gdk.Pixbuf"))
             or type.assignable_to(self.gir.namespaces["Gtk"].lookup_type("Gdk.Texture"))
@@ -136,30 +155,42 @@ class DecompileCtx:
                 self.gir.namespaces["Gtk"].lookup_type("Gtk.ShortcutTrigger")
             )
         ):
-            self.print(f"{name}: {escape_quote(value)};")
+            self.print(f"{escape_quote(value)}")
         elif value == self.template_class:
-            self.print(f"{name}: template;")
+            self.print("template")
         elif type.assignable_to(
             self.gir.namespaces["Gtk"].lookup_type("GObject.Object")
-        ):
-            self.print(f"{name}: {value};")
+        ) or isinstance(type, Interface):
+            self.print(value)
         elif isinstance(type, Bitfield):
             flags = [get_enum_name(flag) for flag in value.split("|")]
-            self.print(f"{name}: {' | '.join(flags)};")
+            self.print(" | ".join(flags))
         elif isinstance(type, Enumeration):
-            self.print(f"{name}: {get_enum_name(value)};")
+            self.print(get_enum_name(value))
+        elif isinstance(type, TypeType):
+            if t := self.type_by_cname(value):
+                self.print(f"typeof<{full_name(t)}>")
+            else:
+                self.print(f"typeof<${value}>")
         else:
-            self.print(f"{name}: {escape_quote(value)};")
+            self.print(f"{escape_quote(value)}")
+
+    def print_attribute(self, name: str, value: str, type: GirType) -> None:
+        self.print(f"{name}: ")
+        self.print_value(value, type)
+        self.print(";")
 
 
-def _decompile_element(
+def decompile_element(
     ctx: DecompileCtx, gir: T.Optional[GirContext], xml: Element
 ) -> None:
     try:
-        decompiler = _DECOMPILERS.get(xml.tag)
-        if decompiler is None:
+        decompilers = [d for d in _DECOMPILERS[xml.tag] if d._filter(ctx)]
+        if len(decompilers) == 0:
             raise UnsupportedError(f"unsupported XML tag: <{xml.tag}>")
 
+        decompiler = decompilers[0]
+
         args: T.Dict[str, T.Optional[str]] = {
             canon(name): value for name, value in xml.attrs.items()
         }
@@ -169,13 +200,16 @@ def _decompile_element(
             else:
                 args["cdata"] = xml.cdata
 
+        ctx._node_stack.append(xml)
         ctx.start_block()
         gir = decompiler(ctx, gir, **args)
 
-        for child in xml.children:
-            _decompile_element(ctx, gir, child)
+        if not decompiler._skip_children:
+            for child in xml.children:
+                decompile_element(ctx, gir, child)
 
         ctx.end_block()
+        ctx._node_stack.pop()
 
     except UnsupportedError as e:
         raise e
@@ -187,7 +221,7 @@ def decompile(data: str) -> str:
     ctx = DecompileCtx()
 
     xml = parse(data)
-    _decompile_element(ctx, None, xml)
+    decompile_element(ctx, None, xml)
 
     return ctx.result
 
@@ -196,7 +230,7 @@ def decompile_string(data):
     ctx = DecompileCtx()
 
     xml = parse_string(data)
-    _decompile_element(ctx, None, xml)
+    decompile_element(ctx, None, xml)
 
     return ctx.result
 
@@ -212,7 +246,7 @@ def truthy(string: str) -> bool:
     return string.lower() in ["yes", "true", "t", "y", "1"]
 
 
-def full_name(gir) -> str:
+def full_name(gir: GirType) -> str:
     return gir.name if gir.full_name.startswith("Gtk.") else gir.full_name
 
 
@@ -223,17 +257,43 @@ def lookup_by_cname(gir, cname: str) -> T.Optional[GirType]:
         return gir.get_containing(Repository).get_type_by_cname(cname)
 
 
-def decompiler(tag, cdata=False):
+def decompiler(
+    tag,
+    cdata=False,
+    parent_type: T.Optional[str] = None,
+    parent_tag: T.Optional[str] = None,
+    skip_children=False,
+):
     def decorator(func):
         func._cdata = cdata
-        _DECOMPILERS[tag] = func
+        func._skip_children = skip_children
+
+        def filter(ctx):
+            if parent_type is not None:
+                if (
+                    ctx.current_obj_type is None
+                    or ctx.current_obj_type.full_name != parent_type
+                ):
+                    return False
+
+            if parent_tag is not None:
+                if not any(x.tag == parent_tag for x in ctx._node_stack):
+                    return False
+
+            return True
+
+        func._filter = filter
+
+        _DECOMPILERS[tag].append(func)
         return func
 
     return decorator
 
 
 @decompiler("interface")
-def decompile_interface(ctx, gir):
+def decompile_interface(ctx, gir, domain=None):
+    if domain is not None:
+        ctx.print(f"translation-domain {escape_quote(domain)};")
     return gir
 
 
@@ -284,7 +344,7 @@ def decompile_property(
         ctx.print(f"/* Translators: {comments} */")
 
     if cdata is None:
-        ctx.print(f"{name}: ", False)
+        ctx.print(f"{name}: ")
         ctx.end_block_with(";")
     elif bind_source:
         flags = ""
@@ -295,6 +355,10 @@ def decompile_property(
             flags += " inverted"
         if "bidirectional" in bind_flags:
             flags += " bidirectional"
+
+        if bind_source == ctx.template_class:
+            bind_source = "template"
+
         ctx.print(f"{name}: bind {bind_source}.{bind_property}{flags};")
     elif truthy(translatable):
         comments, translatable = decompile_translatable(

blueprintcompiler/gir.py

@@ -904,6 +904,10 @@ class Namespace(GirNode):
 
     def get_type_by_cname(self, cname: str) -> T.Optional[GirType]:
         """Gets a type from this namespace by its C name."""
+        for basic in _BASIC_TYPES.values():
+            if basic.glib_type_name == cname:
+                return basic()
+
         for item in self.entries.values():
             if (
                 hasattr(item, "cname")

blueprintcompiler/language/binding.py

@@ -107,3 +107,9 @@ class SimpleBinding:
     no_sync_create: bool = False
     bidirectional: bool = False
     inverted: bool = False
+
+
+@decompiler("binding")
+def decompile_binding(ctx: DecompileCtx, gir: gir.GirContext, name: str):
+    ctx.end_block_with(";")
+    ctx.print(f"{name}: bind ")

blueprintcompiler/language/expression.py

@@ -18,9 +18,9 @@
 # SPDX-License-Identifier: LGPL-3.0-or-later
 
 
+from ..decompiler import decompile_element
 from .common import *
 from .contexts import ScopeCtx, ValueTypeCtx
-from .gtkbuilder_template import Template
 from .types import TypeName
 
 expr = Sequence()
@@ -274,3 +274,69 @@ expr.children = [
     AnyOf(ClosureExpr, LiteralExpr, ["(", Expression, ")"]),
     ZeroOrMore(AnyOf(LookupOp, CastExpr)),
 ]
+
+
+@decompiler("lookup", skip_children=True, cdata=True)
+def decompile_lookup(
+    ctx: DecompileCtx, gir: gir.GirContext, cdata: str, name: str, type: str
+):
+    if t := ctx.type_by_cname(type):
+        type = decompile.full_name(t)
+    else:
+        type = "$" + type
+
+    assert ctx.current_node is not None
+
+    constant = None
+    if len(ctx.current_node.children) == 0:
+        constant = cdata
+    elif (
+        len(ctx.current_node.children) == 1
+        and ctx.current_node.children[0].tag == "constant"
+    ):
+        constant = ctx.current_node.children[0].cdata
+
+    if constant is not None:
+        if constant == ctx.template_class:
+            ctx.print("template." + name)
+        else:
+            ctx.print(constant + "." + name)
+        return
+    else:
+        for child in ctx.current_node.children:
+            decompile.decompile_element(ctx, gir, child)
+
+    ctx.print(f" as <{type}>.{name}")
+
+
+@decompiler("constant", cdata=True)
+def decompile_constant(
+    ctx: DecompileCtx, gir: gir.GirContext, cdata: str, type: T.Optional[str] = None
+):
+    if type is None:
+        if cdata == ctx.template_class:
+            ctx.print("template")
+        else:
+            ctx.print(cdata)
+    else:
+        ctx.print_value(cdata, ctx.type_by_cname(type))
+
+
+@decompiler("closure", skip_children=True)
+def decompile_closure(ctx: DecompileCtx, gir: gir.GirContext, function: str, type: str):
+    if t := ctx.type_by_cname(type):
+        type = decompile.full_name(t)
+    else:
+        type = "$" + type
+
+    ctx.print(f"${function}(")
+
+    assert ctx.current_node is not None
+    for i, node in enumerate(ctx.current_node.children):
+        decompile_element(ctx, gir, node)
+
+        assert ctx.current_node is not None
+        if i < len(ctx.current_node.children) - 1:
+            ctx.print(", ")
+
+    ctx.end_block_with(f") as <{type}>")

blueprintcompiler/language/gobject_object.py

@@ -115,7 +115,7 @@ def validate_parent_type(node, ns: str, name: str, err_msg: str):
 
 
 @decompiler("object")
-def decompile_object(ctx, gir, klass, id=None):
+def decompile_object(ctx: DecompileCtx, gir, klass, id=None):
     gir_class = ctx.type_by_cname(klass)
     klass_name = (
         decompile.full_name(gir_class) if gir_class is not None else "$" + klass
@@ -124,4 +124,5 @@ def decompile_object(ctx, gir, klass, id=None):
         ctx.print(f"{klass_name} {{")
     else:
         ctx.print(f"{klass_name} {id} {{")
+    ctx.push_obj_type(gir_class)
     return gir_class

blueprintcompiler/language/gtk_combo_box_text.py

@@ -89,3 +89,29 @@ class ExtComboBoxItems(AstNode):
 )
 def items_completer(lsp, ast_node, match_variables):
     yield Completion("items", CompletionItemKind.Snippet, snippet="items [$0]")
+
+
+@decompiler("items", parent_type="Gtk.ComboBoxText")
+def decompile_items(ctx: DecompileCtx, gir: gir.GirContext):
+    ctx.print("items [")
+
+
+@decompiler("item", parent_type="Gtk.ComboBoxText", cdata=True)
+def decompile_item(
+    ctx: DecompileCtx,
+    gir: gir.GirContext,
+    cdata: str,
+    id: T.Optional[str] = None,
+    translatable="false",
+    comments=None,
+    context=None,
+):
+    comments, translatable = decompile_translatable(
+        cdata, translatable, context, comments
+    )
+    if comments:
+        ctx.print(comments)
+    if id:
+        ctx.print(f"{id}: ")
+    ctx.print(translatable)
+    ctx.print(",")

blueprintcompiler/language/gtk_menu.py

@@ -266,7 +266,7 @@ def decompile_submenu(ctx, gir, id=None):
         ctx.print("submenu {")
 
 
-@decompiler("item")
+@decompiler("item", parent_tag="menu")
 def decompile_item(ctx, gir, id=None):
     if id:
         ctx.print(f"item {id} {{")

blueprintcompiler/language/gtk_size_group.py

@@ -96,3 +96,13 @@ class ExtSizeGroupWidgets(AstNode):
 )
 def size_group_completer(lsp, ast_node, match_variables):
     yield Completion("widgets", CompletionItemKind.Snippet, snippet="widgets [$0]")
+
+
+@decompiler("widgets")
+def size_group_decompiler(ctx, gir: gir.GirContext):
+    ctx.print("widgets [")
+
+
+@decompiler("widget")
+def widget_decompiler(ctx, gir: gir.GirContext, name: str):
+    ctx.print(name + ",")

blueprintcompiler/language/gtk_string_list.py

@@ -73,3 +73,25 @@ class ExtStringListStrings(AstNode):
 )
 def strings_completer(lsp, ast_node, match_variables):
     yield Completion("strings", CompletionItemKind.Snippet, snippet="strings [$0]")
+
+
+@decompiler("items", parent_type="Gtk.StringList")
+def decompile_strings(ctx: DecompileCtx, gir: gir.GirContext):
+    ctx.print("strings [")
+
+
+@decompiler("item", cdata=True, parent_type="Gtk.StringList")
+def decompile_item(
+    ctx: DecompileCtx,
+    gir: gir.GirContext,
+    translatable="false",
+    comments=None,
+    context=None,
+    cdata=None,
+):
+    comments, translatable = decompile_translatable(
+        cdata, translatable, context, comments
+    )
+    if comments is not None:
+        ctx.print(comments)
+    ctx.print(translatable + ",")

blueprintcompiler/utils.py

@@ -109,14 +109,14 @@ class UnescapeError(Exception):
 
 def escape_quote(string: str) -> str:
     return (
-        "'"
+        '"'
         + (
             string.replace("\\", "\\\\")
-            .replace("'", "\\'")
+            .replace('"', '\\"')
             .replace("\n", "\\n")
             .replace("\t", "\\t")
         )
-        + "'"
+        + '"'
     )