parser: port error set, suspend, switch prong comment tests

Port tests:
- "error set declaration"
- "union(enum(u32)) with assigned enum values"
- "resume from suspend block"
- "comments before error set decl"
- "comments before switch prong"
- "array literal with 1 item on 1 line"
- "comments in statements"

Implement in parser.c:
- suspend statement in expectStatement
- Fix error set decl to store lbrace token (not 0)
- Fix comptime statement to wrap inner expression

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

parser.c

@@ -567,7 +567,7 @@ static AstNodeIndex parsePrimaryTypeExpr(Parser* p) {
         }
         case TOKEN_L_BRACE: {
             const AstTokenIndex error_token = nextToken(p);
-            nextToken(p); // consume {
+            const AstTokenIndex lbrace = nextToken(p);
             while (p->token_tags[p->tok_i] != TOKEN_R_BRACE)
                 p->tok_i++;
             const AstTokenIndex rbrace = nextToken(p);
@@ -575,7 +575,7 @@ static AstNodeIndex parsePrimaryTypeExpr(Parser* p) {
                 (AstNodeItem) {
                     .tag = AST_NODE_ERROR_SET_DECL,
                     .main_token = error_token,
-                    .data = { .lhs = 0, .rhs = rbrace },
+                    .data = { .lhs = lbrace, .rhs = rbrace },
                 });
         }
         default:
@@ -2328,6 +2328,15 @@ static AstNodeIndex expectStatement(Parser* p, bool allow_defer_var) {
                 },
             });
     case TOKEN_KEYWORD_SUSPEND:
+        return addNode(&p->nodes,
+            (AstNodeItem) {
+                .tag = AST_NODE_SUSPEND,
+                .main_token = nextToken(p),
+                .data = {
+                    .lhs = expectBlockExprStatement(p),
+                    .rhs = 0,
+                },
+            });
     case TOKEN_KEYWORD_ENUM:
     case TOKEN_KEYWORD_STRUCT:
     case TOKEN_KEYWORD_UNION:;

parser_test.zig

@@ -3140,6 +3140,114 @@ test "zig fmt: first line comment in struct initializer" {
     );
 }
 
+test "zig fmt: error set declaration" {
+    try testCanonical(
+        \\const E = error{
+        \\    A,
+        \\    B,
+        \\
+        \\    C,
+        \\};
+        \\
+        \\const Error = error{
+        \\    /// no more memory
+        \\    OutOfMemory,
+        \\};
+        \\
+        \\const Error = error{
+        \\    /// no more memory
+        \\    OutOfMemory,
+        \\
+        \\    /// another
+        \\    Another,
+        \\
+        \\    // end
+        \\};
+        \\
+        \\const Error = error{OutOfMemory};
+        \\const Error = error{};
+        \\
+        \\const Error = error{ OutOfMemory, OutOfTime };
+        \\
+    );
+}
+
+test "zig fmt: union(enum(u32)) with assigned enum values" {
+    try testCanonical(
+        \\const MultipleChoice = union(enum(u32)) {
+        \\    A = 20,
+        \\    B = 40,
+        \\    C = 60,
+        \\    D = 1000,
+        \\};
+        \\
+    );
+}
+
+test "zig fmt: resume from suspend block" {
+    try testCanonical(
+        \\fn foo() void {
+        \\    suspend {
+        \\        resume @frame();
+        \\    }
+        \\}
+        \\
+    );
+}
+
+test "zig fmt: comments before error set decl" {
+    try testCanonical(
+        \\const UnexpectedError = error{
+        \\    /// The Operating System returned an undocumented error code.
+        \\    Unexpected,
+        \\    // another
+        \\    Another,
+        \\
+        \\    // in between
+        \\
+        \\    // at end
+        \\};
+        \\
+    );
+}
+
+test "zig fmt: comments before switch prong" {
+    try testCanonical(
+        \\test "" {
+        \\    switch (err) {
+        \\        error.PathAlreadyExists => continue,
+        \\
+        \\        // comment 1
+        \\
+        \\        // comment 2
+        \\        else => return err,
+        \\        // at end
+        \\    }
+        \\}
+        \\
+    );
+}
+
+test "zig fmt: array literal with 1 item on 1 line" {
+    try testCanonical(
+        \\var s = []const u64{0} ** 25;
+        \\
+    );
+}
+
+test "zig fmt: comments in statements" {
+    try testCanonical(
+        \\comptime {
+        \\    // a
+        \\
+        \\    const x = 42; // b
+        \\
+        \\    // c
+        \\}
+        \\
+    );
+}
+
 test "zig fmt: doc comments before struct field" {
     try testCanonical(
         \\pub const Allocator = struct {