tiny.chant.parse.assertion

1const std = @import("std");2const expression = @import("expression.zig");3const state = @import("state/root.zig");45const cursor = state.cursor;6const diagnostic = state.diagnostic;7const Error = @import("error.zig").Error;8const Parser = state.Parser;910pub fn consume(parser: *Parser) Error!bool {11    if (!cursor.consume(parser, .kw_static_assert)) return false;12    _ = try cursor.expect(parser, .lparen);13    const condition = try expression.parseExpression(parser);14    const value = expression.evaluateIntegerConstant(parser, condition) orelse15        return diagnostic.fail(parser, error.UnsupportedConstruct, "static_assert condition is not an integer constant");16    if (cursor.consume(parser, .comma)) {17        _ = try cursor.expect(parser, .string);18    }19    _ = try cursor.expect(parser, .rparen);20    _ = try cursor.expect(parser, .semicolon);21    if (value == 0) {22        return diagnostic.fail(parser, error.StaticAssertionFailed, "static assertion failed");23    }24    return true;25}2627test "static assertions accept nonzero integer constants" {28    const lexer = @import("../lexer/root.zig");29    var arena_state = std.heap.ArenaAllocator.init(std.testing.allocator);30    defer arena_state.deinit();31    const arena = arena_state.allocator();3233    const source = "static_assert(alignof(double) == 8, \"lp64\");";34    const token_survey = try lexer.survey(source, "assert.c");35    const capacity = try lexer.Capacity.derive(token_survey.limits);36    const bytes = try arena.alignedAlloc(37        u8,38        .fromByteUnits(lexer.Storage.storage_alignment),39        capacity.storage_bytes,40    );41    var storage = try lexer.Storage.init(bytes, token_survey.limits);42    storage.activate();43    defer _ = storage.deinit();44    const tokens = try storage.fill(token_survey, source, "assert.c");45    var parser = try @import("state/test.zig").initParser(arena, tokens);46    try std.testing.expect(try consume(&parser));47}4849test "static assertions reject zero" {50    const lexer = @import("../lexer/root.zig");51    var arena_state = std.heap.ArenaAllocator.init(std.testing.allocator);52    defer arena_state.deinit();53    const arena = arena_state.allocator();5455    const source = "static_assert(false);";56    const token_survey = try lexer.survey(source, "assert.c");57    const capacity = try lexer.Capacity.derive(token_survey.limits);58    const bytes = try arena.alignedAlloc(59        u8,60        .fromByteUnits(lexer.Storage.storage_alignment),61        capacity.storage_bytes,62    );63    var storage = try lexer.Storage.init(bytes, token_survey.limits);64    storage.activate();65    defer _ = storage.deinit();66    const tokens = try storage.fill(token_survey, source, "assert.c");67    var parser = try @import("state/test.zig").initParser(arena, tokens);68    try std.testing.expectError(error.StaticAssertionFailed, consume(&parser));69}

1pub const assertion = @import("assert.zig");