lsp: Add reference documentation on hover

For most constructs and keywords, show the relevant section of the
reference documentation on hover.

blueprintcompiler/ast_utils.py

@@ -179,14 +179,16 @@ class AstNode:
                 token = self.group.tokens.get(attr.token_name)
                 if token and token.start <= idx < token.end:
                     return getattr(self, name)
-            else:
-                return getattr(self, name)
 
         for child in self.children:
             if idx in child.range:
                 if docs := child.get_docs(idx):
                     return docs
 
+        for name, attr in self._attrs_by_type(Docs):
+            if not attr.token_name:
+                return getattr(self, name)
+
         return None
 
     def get_semantic_tokens(self) -> T.Iterator[SemanticToken]:

blueprintcompiler/language/adw_breakpoint.py

@@ -207,6 +207,10 @@ class AdwBreakpointSetters(AstNode):
     def unique(self):
         self.validate_unique_in_parent("Duplicate setters block")
 
+    @docs("setters")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtAdwBreakpoint")
+
 
 @decompiler("condition", cdata=True)
 def decompile_condition(ctx: DecompileCtx, gir, cdata):

blueprintcompiler/language/adw_response_dialog.py

@@ -138,6 +138,10 @@ class ExtAdwResponseDialog(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate responses block")
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtAdwMessageDialog")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/binding.py

@@ -58,6 +58,10 @@ class BindingFlag(AstNode):
                 "Only bindings with a single lookup can have flags",
             )
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax Binding")
+
 
 class Binding(AstNode):
     grammar = [
@@ -99,6 +103,10 @@ class Binding(AstNode):
                 actions=[CodeAction("use 'bind'", "bind")],
             )
 
+    @docs("bind")
+    def ref_docs(self):
+        return get_docs_section("Syntax Binding")
+
 
 @dataclass
 class SimpleBinding:

blueprintcompiler/language/common.py

@@ -55,6 +55,7 @@ from ..lsp_utils import (
     SemanticToken,
     SemanticTokenType,
     SymbolKind,
+    get_docs_section,
 )
 from ..parse_tree import *
 

blueprintcompiler/language/expression.py

@@ -174,7 +174,7 @@ class LookupOp(InfixExpr):
 
 class CastExpr(InfixExpr):
     grammar = [
-        "as",
+        Keyword("as"),
         AnyOf(
             ["<", TypeName, Match(">").expected()],
             [
@@ -220,6 +220,10 @@ class CastExpr(InfixExpr):
                 ],
             )
 
+    @docs("as")
+    def ref_docs(self):
+        return get_docs_section("Syntax CastExpression")
+
 
 class ClosureArg(AstNode):
     grammar = Expression
@@ -269,6 +273,10 @@ class ClosureExpr(ExprBase):
         if not self.tokens["extern"]:
             raise CompileError(f"{self.closure_name} is not a builtin function")
 
+    @docs("name")
+    def ref_docs(self):
+        return get_docs_section("Syntax ClosureExpression")
+
 
 expr.children = [
     AnyOf(ClosureExpr, LiteralExpr, ["(", Expression, ")"]),

blueprintcompiler/language/gobject_signal.py

@@ -40,6 +40,10 @@ class SignalFlag(AstNode):
             f"Duplicate flag '{self.flag}'", lambda x: x.flag == self.flag
         )
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax Signal")
+
 
 class Signal(AstNode):
     grammar = Statement(
@@ -50,7 +54,7 @@ class Signal(AstNode):
                 UseIdent("detail_name").expected("a signal detail name"),
             ]
         ),
-        "=>",
+        Keyword("=>"),
         Mark("detail_start"),
         Optional(["$", UseLiteral("extern", True)]),
         UseIdent("handler").expected("the name of a function to handle the signal"),
@@ -184,6 +188,10 @@ class Signal(AstNode):
                 if prop is not None:
                     return prop.doc
 
+    @docs("=>")
+    def ref_docs(self):
+        return get_docs_section("Syntax Signal")
+
 
 @decompiler("signal")
 def decompile_signal(

blueprintcompiler/language/gtk_a11y.py

@@ -225,6 +225,10 @@ class ExtAccessibility(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate accessibility block")
 
+    @docs("accessibility")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtAccessibility")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_combo_box_text.py

@@ -55,6 +55,10 @@ class Item(AstNode):
                 f"Duplicate item '{self.name}'", lambda x: x.name == self.name
             )
 
+    @docs("name")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtComboBoxItems")
+
 
 class ExtComboBoxItems(AstNode):
     grammar = [
@@ -81,6 +85,10 @@ class ExtComboBoxItems(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate items block")
 
+    @docs("items")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtComboBoxItems")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_file_filter.py

@@ -29,25 +29,23 @@ class Filters(AstNode):
             self.tokens["tag_name"],
             SymbolKind.Array,
             self.range,
-            self.group.tokens[self.tokens["tag_name"]].range,
+            self.group.tokens["tag_name"].range,
         )
 
     @validate()
     def container_is_file_filter(self):
         validate_parent_type(self, "Gtk", "FileFilter", "file filter properties")
 
-    @validate()
+    @validate("tag_name")
     def unique_in_parent(self):
-        # The token argument to validate() needs to be calculated based on
-        # the instance, hence wrapping it like this.
-        @validate(self.tokens["tag_name"])
-        def wrapped_validator(self):
-            self.validate_unique_in_parent(
-                f"Duplicate {self.tokens['tag_name']} block",
-                check=lambda child: child.tokens["tag_name"] == self.tokens["tag_name"],
-            )
+        self.validate_unique_in_parent(
+            f"Duplicate {self.tokens['tag_name']} block",
+            check=lambda child: child.tokens["tag_name"] == self.tokens["tag_name"],
+        )
 
-        wrapped_validator(self)
+    @docs("tag_name")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtFileFilter")
 
 
 class FilterString(AstNode):
@@ -76,8 +74,7 @@ def create_node(tag_name: str, singular: str):
     return Group(
         Filters,
         [
-            Keyword(tag_name),
-            UseLiteral("tag_name", tag_name),
+            UseExact("tag_name", tag_name),
             "[",
             Delimited(
                 Group(

blueprintcompiler/language/gtk_layout.py

@@ -83,6 +83,10 @@ class ExtLayout(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate layout block")
 
+    @docs("layout")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtLayout")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_list_item_factory.py

@@ -108,3 +108,7 @@ class ExtListItemFactory(AstNode):
         just hear to satisfy XmlOutput._emit_object_or_template
         """
         return None
+
+    @docs("id")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtListItemFactory")

blueprintcompiler/language/gtk_menu.py

@@ -70,6 +70,25 @@ class Menu(AstNode):
         if self.id in RESERVED_IDS:
             raise CompileWarning(f"{self.id} may be a confusing object ID")
 
+    @docs("menu")
+    def ref_docs_menu(self):
+        return get_docs_section("Syntax Menu")
+
+    @docs("section")
+    def ref_docs_section(self):
+        return get_docs_section("Syntax Menu")
+
+    @docs("submenu")
+    def ref_docs_submenu(self):
+        return get_docs_section("Syntax Menu")
+
+    @docs("item")
+    def ref_docs_item(self):
+        if self.tokens["shorthand"]:
+            return get_docs_section("Syntax MenuItemShorthand")
+        else:
+            return get_docs_section("Syntax Menu")
+
 
 class MenuAttribute(AstNode):
     tag_name = "attribute"
@@ -156,6 +175,7 @@ menu_item_shorthand = Group(
     [
         Keyword("item"),
         UseLiteral("tag", "item"),
+        UseLiteral("shorthand", True),
         "(",
         Group(
             MenuAttribute,

blueprintcompiler/language/gtk_scale.py

@@ -94,6 +94,10 @@ class ExtScaleMark(AstNode):
                 did_you_mean=(self.position, positions.keys()),
             )
 
+    @docs("mark")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtScaleMarks")
+
 
 class ExtScaleMarks(AstNode):
     grammar = [
@@ -123,6 +127,10 @@ class ExtScaleMarks(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate 'marks' block")
 
+    @docs("marks")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtScaleMarks")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_size_group.py

@@ -94,6 +94,10 @@ class ExtSizeGroupWidgets(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate widgets block")
 
+    @docs("widgets")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtSizeGroupWidgets")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_string_list.py

@@ -57,7 +57,7 @@ class ExtStringListStrings(AstNode):
             self.group.tokens["strings"].range,
         )
 
-    @validate("items")
+    @validate("strings")
     def container_is_string_list(self):
         validate_parent_type(self, "Gtk", "StringList", "StringList items")
 
@@ -65,6 +65,10 @@ class ExtStringListStrings(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate strings block")
 
+    @docs("strings")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtStringListStrings")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtk_styles.py

@@ -70,6 +70,10 @@ class ExtStyles(AstNode):
     def unique_in_parent(self):
         self.validate_unique_in_parent("Duplicate styles block")
 
+    @docs("styles")
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtStyles")
+
 
 @completer(
     applies_in=[ObjectContent],

blueprintcompiler/language/gtkbuilder_child.py

@@ -53,6 +53,10 @@ class ChildExtension(AstNode):
     def child(self) -> ExtResponse:
         return self.children[0]
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax ChildExtension")
+
 
 class ChildAnnotation(AstNode):
     grammar = ["[", AnyOf(ChildInternal, ChildExtension, ChildType), "]"]

blueprintcompiler/language/gtkbuilder_template.py

@@ -88,6 +88,10 @@ class Template(Object):
             f"Only one template may be defined per file, but this file contains {len(self.parent.children[Template])}",
         )
 
+    @docs("id")
+    def ref_docs(self):
+        return get_docs_section("Syntax Template")
+
 
 @decompiler("template")
 def decompile_template(ctx: DecompileCtx, gir, klass, parent=None):

blueprintcompiler/language/imports.py

@@ -68,6 +68,10 @@ class GtkDirective(AstNode):
             # For better error handling, just assume it's 4.0
             return gir.get_namespace("Gtk", "4.0")
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax GtkDecl")
+
 
 class Import(AstNode):
     grammar = Statement(
@@ -105,3 +109,7 @@ class Import(AstNode):
             return gir.get_namespace(self.tokens["namespace"], self.tokens["version"])
         except CompileError:
             return None
+
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax Using")

blueprintcompiler/language/response_id.py

@@ -124,6 +124,16 @@ class ExtResponse(AstNode):
         object = self.parent_by_type(Child).object
         return object.id
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax ExtResponse")
+
+    @docs("response_id")
+    def response_id_docs(self):
+        if enum := self.root.gir.get_type("ResponseType", "Gtk"):
+            if member := enum.members.get(self.response_id, None):
+                return member.doc
+
 
 def decompile_response_type(parent_element, child_element):
     obj_id = None

blueprintcompiler/language/translation_domain.py

@@ -29,3 +29,7 @@ class TranslationDomain(AstNode):
     @property
     def domain(self):
         return self.tokens["domain"]
+
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax TranslationDomain")

blueprintcompiler/language/values.py

@@ -20,6 +20,7 @@
 import typing as T
 
 from blueprintcompiler.gir import ArrayType
+from blueprintcompiler.lsp_utils import SemanticToken
 
 from .common import *
 from .contexts import ScopeCtx, ValueTypeCtx
@@ -56,6 +57,10 @@ class Translated(AstNode):
                 f"Cannot convert translated string to {expected_type.full_name}"
             )
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax Translated")
+
 
 class TypeLiteral(AstNode):
     grammar = [
@@ -101,6 +106,10 @@ class TypeLiteral(AstNode):
                 ],
             )
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax TypeLiteral")
+
 
 class QuotedLiteral(AstNode):
     grammar = UseQuoted("value")
@@ -258,6 +267,10 @@ class Flags(AstNode):
         if expected_type is not None and not isinstance(expected_type, gir.Bitfield):
             raise CompileError(f"{expected_type.full_name} is not a bitfield type")
 
+    @docs()
+    def ref_docs(self):
+        return get_docs_section("Syntax Flags")
+
 
 class IdentLiteral(AstNode):
     grammar = UseIdent("value")

blueprintcompiler/lsp_utils.py

@@ -19,6 +19,8 @@
 
 
 import enum
+import json
+import os
 import typing as T
 from dataclasses import dataclass, field
 
@@ -200,3 +202,27 @@ class TextEdit:
 
     def to_json(self):
         return {"range": self.range.to_json(), "newText": self.newText}
+
+
+_docs_sections: T.Optional[dict[str, T.Any]] = None
+
+
+def get_docs_section(section_name: str) -> T.Optional[str]:
+    global _docs_sections
+
+    if _docs_sections is None:
+        try:
+            with open(
+                os.path.join(os.path.dirname(__file__), "reference_docs.json")
+            ) as f:
+                _docs_sections = json.load(f)
+        except FileNotFoundError:
+            _docs_sections = {}
+
+    if section := _docs_sections.get(section_name):
+        content = section["content"]
+        link = section["link"]
+        content += f"\n\n---\n\n[Online documentation]({link})"
+        return content
+    else:
+        return None

docs/collect-sections.py

@@ -0,0 +1,136 @@
+#!/usr/bin/env python3
+
+import json
+import os
+import re
+import sys
+from dataclasses import dataclass
+from pathlib import Path
+
+__all__ = ["get_docs_section"]
+
+DOCS_ROOT = "https://jwestman.pages.gitlab.gnome.org/blueprint-compiler"
+
+
+sections: dict[str, "Section"] = {}
+
+
+@dataclass
+class Section:
+    link: str
+    lines: str
+
+    def to_json(self):
+        return {
+            "content": rst_to_md(self.lines),
+            "link": self.link,
+        }
+
+
+def load_reference_docs():
+    for filename in Path(os.path.dirname(__file__), "reference").glob("*.rst"):
+        with open(filename) as f:
+            section_name = None
+            lines = []
+
+            def close_section():
+                if section_name:
+                    html_file = re.sub(r"\.rst$", ".html", filename.name)
+                    anchor = re.sub(r"[^a-z0-9]+", "-", section_name.lower())
+                    link = f"{DOCS_ROOT}/reference/{html_file}#{anchor}"
+                    sections[section_name] = Section(link, lines)
+
+            for line in f:
+                if m := re.match(r"\.\.\s+_(.*):", line):
+                    close_section()
+                    section_name = m.group(1)
+                    lines = []
+                else:
+                    lines.append(line)
+
+            close_section()
+
+
+# This isn't a comprehensive rST to markdown converter, it just needs to handle the
+# small subset of rST used in the reference docs.
+def rst_to_md(lines: list[str]) -> str:
+    result = ""
+
+    def rst_to_md_inline(line):
+        line = re.sub(r"``(.*?)``", r"`\1`", line)
+        line = re.sub(
+            r":ref:`(.*?)<(.*?)>`",
+            lambda m: f"[{m.group(1)}]({sections[m.group(2)].link})",
+            line,
+        )
+        line = re.sub(r"`([^`]*?) <([^`>]*?)>`_", r"[\1](\2)", line)
+        return line
+
+    i = 0
+    n = len(lines)
+    heading_levels = {}
+
+    def print_block(lang: str = "", code: bool = True, strip_links: bool = False):
+        nonlocal result, i
+        block = ""
+        while i < n:
+            line = lines[i].rstrip()
+            if line.startswith("   "):
+                line = line[3:]
+            elif line != "":
+                break
+
+            if strip_links:
+                line = re.sub(r":ref:`(.*?)<(.*?)>`", r"\1", line)
+
+            if not code:
+                line = rst_to_md_inline(line)
+
+            block += line + "\n"
+            i += 1
+
+        if code:
+            result += f"```{lang}\n{block.strip()}\n```\n\n"
+        else:
+            result += block
+
+    while i < n:
+        line = lines[i].rstrip()
+        i += 1
+        if line == ".. rst-class:: grammar-block":
+            print_block(strip_links=True)
+        elif line == ".. code-block:: blueprint":
+            print_block("blueprint")
+        elif line == ".. note::":
+            result += "#### Note\n"
+            print_block(code=False)
+        elif m := re.match(r"\.\. image:: (.*)", line):
+            result += f"![{m.group(1)}]({DOCS_ROOT}/_images/{m.group(1)})\n"
+        elif i < n and re.match(r"^((-+)|(~+)|(\++))$", lines[i]):
+            level_char = lines[i][0]
+            if level_char not in heading_levels:
+                heading_levels[level_char] = max(heading_levels.values(), default=1) + 1
+            result += (
+                "#" * heading_levels[level_char] + " " + rst_to_md_inline(line) + "\n"
+            )
+            i += 1
+        else:
+            result += rst_to_md_inline(line) + "\n"
+
+    return result
+
+
+if __name__ == "__main__":
+    if len(sys.argv) != 2:
+        print("Usage: collect_sections.py <output_file>")
+        sys.exit(1)
+
+    outfile = sys.argv[1]
+
+    load_reference_docs()
+
+    # print the sections to a json file
+    with open(outfile, "w") as f:
+        json.dump(
+            {name: section.to_json() for name, section in sections.items()}, f, indent=2
+        )

docs/meson.build

@@ -9,3 +9,11 @@ custom_target('docs',
 )
 
 endif
+
+custom_target('reference_docs.json',
+  output: 'reference_docs.json',
+  command: [meson.current_source_dir() / 'collect-sections.py', '@OUTPUT@'],
+  build_always_stale: true,
+  install: true,
+  install_dir: py.get_install_dir() / 'blueprintcompiler',
+)

docs/reference/extensions.rst

@@ -227,7 +227,7 @@ Valid in `Gtk.BuilderListItemFactory <https://docs.gtk.org/gtk4/class.BuilderLis
 
 The ``template`` block defines the template that will be used to create list items. This block is unique within Blueprint because it defines a completely separate sub-blueprint which is used to create each list item. The sub-blueprint may not reference objects in the main blueprint or vice versa.
 
-The template type must be `Gtk.ListItem <https://docs.gtk.org/gtk4/class.ListItem.html>`_, `Gtk.ColumnViewRow <https://docs.gtk.org/gtk4/class.ColumnViewRow.html>`_, or `Gtk.ColumnViewCell <https://docs.gtk.org/gtk4/class.ColumnViewCell.html>`_ The template object can be referenced with the ``template`` keyword.
+The template type must be `Gtk.ListItem <https://docs.gtk.org/gtk4/class.ListItem.html>`_, `Gtk.ColumnViewRow <https://docs.gtk.org/gtk4/class.ColumnViewRow.html>`_, or `Gtk.ColumnViewCell <https://docs.gtk.org/gtk4/class.ColumnViewCell.html>`_. The template object can be referenced with the ``template`` keyword.
 
 .. code-block:: blueprint
 

meson.build

@@ -2,13 +2,13 @@ project('blueprint-compiler',
   version: '0.14.0',
 )
 
-subdir('docs')
-
 prefix = get_option('prefix')
 datadir = join_paths(prefix, get_option('datadir'))
 
 py = import('python').find_installation('python3')
 
+subdir('docs')
+
 configure_file(
   input: 'blueprint-compiler.pc.in',
   output: 'blueprint-compiler.pc',