zig

commit 11a4ce42c16c17422cd272f154c9c33231bcc61a (tree)
parent 63a4dbc30d3ef3c7f8a8c6a2ba2087eaab8b830a
Author: LemonBoy <thatlemon@gmail.com>
Date:   Fri, 28 Feb 2020 12:06:43 +0100

zig fmt: Respect trailing commas in error set declarations

The logic is not perfect as it doesn't take into account the presence of
doc comments, but it's an improvement over the status quo.

Diffstat:
M
lib/std/zig/parser_test.zig
 | 
2
++
M
lib/std/zig/render.zig
 | 
58
+++++++++++++++++++++++++++++++++++++++++-----------------

2 files changed, 43 insertions(+), 17 deletions(-)
diff --git a/lib/std/zig/parser_test.zig b/lib/std/zig/parser_test.zig
@@ -1509,6 +1509,8 @@ test "zig fmt: error set declaration" {
         \\const Error = error{OutOfMemory};
         \\const Error = error{};
         \\
+        \\const Error = error{ OutOfMemory, OutOfTime };
+        \\
     );
 }
 
diff --git a/lib/std/zig/render.zig b/lib/std/zig/render.zig
@@ -1268,25 +1268,51 @@ fn renderExpression(
             }
 
             try renderToken(tree, stream, err_set_decl.error_token, indent, start_col, Space.None); // error
-            try renderToken(tree, stream, lbrace, indent, start_col, Space.Newline); // {
-            const new_indent = indent + indent_delta;
 
-            var it = err_set_decl.decls.iterator(0);
-            while (it.next()) |node| {
-                try stream.writeByteNTimes(' ', new_indent);
+            const src_has_trailing_comma = blk: {
+                const maybe_comma = tree.prevToken(err_set_decl.rbrace_token);
+                break :blk tree.tokens.at(maybe_comma).id == .Comma;
+            };
 
-                if (it.peek()) |next_node| {
-                    try renderExpression(allocator, stream, tree, new_indent, start_col, node.*, Space.None);
-                    try renderToken(tree, stream, tree.nextToken(node.*.lastToken()), new_indent, start_col, Space.Newline); // ,
+            if (src_has_trailing_comma) {
+                try renderToken(tree, stream, lbrace, indent, start_col, Space.Newline); // {
+                const new_indent = indent + indent_delta;
 
-                    try renderExtraNewline(tree, stream, start_col, next_node.*);
-                } else {
-                    try renderExpression(allocator, stream, tree, new_indent, start_col, node.*, Space.Comma);
+                var it = err_set_decl.decls.iterator(0);
+                while (it.next()) |node| {
+                    try stream.writeByteNTimes(' ', new_indent);
+
+                    if (it.peek()) |next_node| {
+                        try renderExpression(allocator, stream, tree, new_indent, start_col, node.*, Space.None);
+                        try renderToken(tree, stream, tree.nextToken(node.*.lastToken()), new_indent, start_col, Space.Newline); // ,
+
+                        try renderExtraNewline(tree, stream, start_col, next_node.*);
+                    } else {
+                        try renderExpression(allocator, stream, tree, new_indent, start_col, node.*, Space.Comma);
+                    }
                 }
-            }
 
-            try stream.writeByteNTimes(' ', indent);
-            return renderToken(tree, stream, err_set_decl.rbrace_token, indent, start_col, space); // }
+                try stream.writeByteNTimes(' ', indent);
+                return renderToken(tree, stream, err_set_decl.rbrace_token, indent, start_col, space); // }
+            } else {
+                try renderToken(tree, stream, lbrace, indent, start_col, Space.Space); // {
+
+                var it = err_set_decl.decls.iterator(0);
+                while (it.next()) |node| {
+                    if (it.peek()) |next_node| {
+                        try renderExpression(allocator, stream, tree, indent, start_col, node.*, Space.None);
+
+                        const comma_token = tree.nextToken(node.*.lastToken());
+                        assert(tree.tokens.at(comma_token).id == .Comma);
+                        try renderToken(tree, stream, comma_token, indent, start_col, Space.Space); // ,
+                        try renderExtraNewline(tree, stream, start_col, next_node.*);
+                    } else {
+                        try renderExpression(allocator, stream, tree, indent, start_col, node.*, Space.Space);
+                    }
+                }
+
+                return renderToken(tree, stream, err_set_decl.rbrace_token, indent, start_col, space); // }
+            }
         },
 
         .ErrorTag => {
@@ -1589,8 +1615,7 @@ fn renderExpression(
                 }
             } else {
                 var it = switch_case.items.iterator(0);
-                while (true) {
-                    const node = it.next().?;
+                while (it.next()) |node| {
                     if (it.peek()) |next_node| {
                         try renderExpression(allocator, stream, tree, indent, start_col, node.*, Space.None);
 
@@ -1601,7 +1626,6 @@ fn renderExpression(
                     } else {
                         try renderExpression(allocator, stream, tree, indent, start_col, node.*, Space.Comma);
                         try stream.writeByteNTimes(' ', indent);
-                        break;
                     }
                 }
             }