Files
browser/src/browser/webapi/XPathExpression.zig
Navid EMAD 94bcee6322 xpath: apply review style/convention feedback
- Rename Result.zig / Ast.zig / Functions.zig to snake_case (no
  top-level fields per Zig style guide)
- Restructure imports across xpath module: lib (std/lp) → relative
  (further → nearer) → aliases
- Move `frame` to last parameter on Evaluator.evaluate, searchAll,
  Functions.call, idFn (matches js bridge convention); call sites
  updated in webapi/XPath{Result,Expression}.zig and cdp/domains/dom.zig
- Local-pos style in XPathResult.iterateNext
2026-05-08 08:44:31 +02:00

106 lines
3.6 KiB
Zig

// Copyright (C) 2023-2026 Lightpanda (Selecy SAS)
//
// Francis Bouvier <francis@lightpanda.io>
// Pierre Tachoire <pierre@lightpanda.io>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
//! WHATWG `XPathExpression` — a parsed XPath expression cached for
//! repeated evaluation. The parsed AST lives in this object's per-
//! instance arena (long-lived); each `evaluate()` call gets a fresh
//! arena for its own result data so multiple evaluations don't grow
//! the AST arena.
const std = @import("std");
const lp = @import("lightpanda");
const js = @import("../js/js.zig");
const Page = @import("../Page.zig");
const Frame = @import("../Frame.zig");
const Node = @import("Node.zig");
const XPathResult = @import("XPathResult.zig");
const xpath = struct {
const Ast = @import("../xpath/ast.zig");
const Parser = @import("../xpath/Parser.zig");
const Evaluator = @import("../xpath/Evaluator.zig");
};
const Allocator = std.mem.Allocator;
const XPathExpression = @This();
_rc: lp.RC(u8) = .{},
_arena: Allocator,
_expr: *const xpath.Ast.Expr,
pub fn init(expression: []const u8, frame: *Frame) !*XPathExpression {
const arena = try frame.getArena(.tiny, "XPathExpression");
errdefer frame.releaseArena(arena);
// The AST borrows string slices from its input (literals, names,
// var refs, function names). `expression` is materialized in the JS
// call_arena and is reclaimed when the top-level call returns, so
// dupe into our long-lived arena before parsing.
const owned = try arena.dupe(u8, expression);
const expr = try xpath.Parser.parse(arena, owned);
const xe = try arena.create(XPathExpression);
xe.* = .{ ._arena = arena, ._expr = expr };
return xe;
}
pub fn evaluate(
self: *XPathExpression,
context_node: *Node,
requested_type: u16,
result: ?*XPathResult,
frame: *Frame,
) !*XPathResult {
// The `result` reuse parameter (WHATWG: optional XPathResult to
// populate) is accepted-and-ignored: we always allocate fresh,
// which matches every modern browser's effective behavior.
_ = result;
const arena = try frame.getArena(.medium, "XPathResult");
errdefer frame.releaseArena(arena);
const eval_result = try xpath.Evaluator.evaluate(arena, self._expr, context_node, frame);
return XPathResult.fromResult(arena, requested_type, eval_result);
}
pub fn deinit(self: *XPathExpression, page: *Page) void {
page.releaseArena(self._arena);
}
pub fn acquireRef(self: *XPathExpression) void {
self._rc.acquire();
}
pub fn releaseRef(self: *XPathExpression, page: *Page) void {
self._rc.release(self, page);
}
pub const JsApi = struct {
pub const bridge = js.Bridge(XPathExpression);
pub const Meta = struct {
pub const name = "XPathExpression";
pub const prototype_chain = bridge.prototypeChain();
pub var class_id: bridge.ClassId = undefined;
};
pub const evaluate = bridge.function(XPathExpression.evaluate, .{ .dom_exception = true });
};