parser: port fn param and container initializer tests

Port tests:
- "doc comments on param decl"
- "pointer of unknown length"
- "call expression"
- "anytype type"
- "container initializers"

Handle anytype keyword in function parameter lists.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

parser.c

@@ -1113,7 +1113,7 @@ static SmallSpan parseParamDeclList(Parser* p) {
             && p->token_tags[p->tok_i + 1] == TOKEN_COLON) {
             p->tok_i += 2; // consume name and colon
         } else if (p->token_tags[p->tok_i] == TOKEN_ELLIPSIS3) {
-            // anytype (...) varargs
+            // varargs (...)
             p->tok_i++;
             if (eatToken(p, TOKEN_R_PAREN) != null_token)
                 break;
@@ -1121,6 +1121,16 @@ static SmallSpan parseParamDeclList(Parser* p) {
             continue;
         }
 
+        // anytype params are omitted from the AST
+        if (eatToken(p, TOKEN_KEYWORD_ANYTYPE) != null_token) {
+            if (p->token_tags[p->tok_i] == TOKEN_COMMA) {
+                p->tok_i++;
+                continue;
+            }
+            expectToken(p, TOKEN_R_PAREN);
+            break;
+        }
+
         const AstNodeIndex type_expr = parseTypeExpr(p);
         if (type_expr != 0)
             SLICE_APPEND(AstNodeIndex, &p->scratch, type_expr);

parser_test.zig

@@ -2098,6 +2098,73 @@ test "zig fmt: comment after params" {
     );
 }
 
+test "zig fmt: doc comments on param decl" {
+    try testCanonical(
+        \\pub const Allocator = struct {
+        \\    shrinkFn: fn (
+        \\        self: Allocator,
+        \\        /// Guaranteed to be the same as what was returned from most recent call to
+        \\        /// `allocFn`, `reallocFn`, or `shrinkFn`.
+        \\        old_mem: []u8,
+        \\        /// Guaranteed to be the same as what was returned from most recent call to
+        \\        /// `allocFn`, `reallocFn`, or `shrinkFn`.
+        \\        old_alignment: u29,
+        \\        /// Guaranteed to be less than or equal to `old_mem.len`.
+        \\        new_byte_count: usize,
+        \\        /// Guaranteed to be less than or equal to `old_alignment`.
+        \\        new_alignment: u29,
+        \\    ) []u8,
+        \\};
+        \\
+    );
+}
+
+test "zig fmt: pointer of unknown length" {
+    try testCanonical(
+        \\fn foo(ptr: [*]u8) void {}
+        \\
+    );
+}
+
+test "zig fmt: call expression" {
+    try testCanonical(
+        \\test "test calls" {
+        \\    a();
+        \\    a(1);
+        \\    a(1, 2);
+        \\    a(1, 2) + a(1, 2);
+        \\}
+        \\
+    );
+}
+
+test "zig fmt: anytype type" {
+    try testCanonical(
+        \\fn print(args: anytype) @This() {}
+        \\
+    );
+}
+
+test "zig fmt: container initializers" {
+    try testCanonical(
+        \\const a0 = []u8{};
+        \\const a1 = []u8{1};
+        \\const a2 = []u8{
+        \\    1,
+        \\    2,
+        \\    3,
+        \\    4,
+        \\};
+        \\const s0 = S{};
+        \\const s1 = S{ .a = 1 };
+        \\const s2 = S{
+        \\    .a = 1,
+        \\    .b = 2,
+        \\};
+        \\
+    );
+}
+
 test "zig fmt: sentinel-terminated array type" {
     try testCanonical(
         \\pub fn cStrToPrefixedFileW(s: [*:0]const u8) ![PATH_MAX_WIDE:0]u16 {