Commit a130eac7857512db50320fb1c64079b0d696885d | zig

author	tjohnes <tom@johnes.me> 2021-10-25 09:59:45+01:00
committer	Andrew Kelley <andrew@ziglang.org> 2021-11-24 18:45:09-08:00
log	a130eac7857512db50320fb1c64079b0d696885d
tree	f886cd204f4e5d6657161f3d8f26cbfd18e1c4ca
parent	36c8adf58922d8e357bbaf7ce914cfd4b7b56354

zig fmt: fix formatting for single-line containers with comments

* Fixes #8810.
* Prevent a single-line container declaration if it contains a comment
  or multiline string.
* If a container declaration cannot be single-line, ensure container
  fields are rendered with a trailing comma.
* If `Space.comma` is passed to `renderExpressionComma` or
  `renderTokenComma`, and there already exists a comma in the source,
  then render one comma instead of two.

2 files changed, 67 insertions(+), 5 deletions(-)

lib
- std
  - zig
    parser_test.zig
    render.zig

lib/std/zig/parser_test.zig+44

...	@@ -329,6 +329,50 @@ test "zig fmt: container declaration, transform trailing comma" {	...	@@ -329,6 +329,50 @@ test "zig fmt: container declaration, transform trailing comma" {
329	);	329	);
330	}	330	}
331		331
		332	test "zig fmt: container declaration, comment, add trailing comma" {
		333	try testTransform(
		334	\\const X = struct {
		335	\\ foo: i32, // foo
		336	\\ bar: i8
		337	\\};
		338	,
		339	\\const X = struct {
		340	\\ foo: i32, // foo
		341	\\ bar: i8,
		342	\\};
		343	\\
		344	);
		345	try testTransform(
		346	\\const X = struct {
		347	\\ foo: i32 // foo
		348	\\};
		349	,
		350	\\const X = struct {
		351	\\ foo: i32, // foo
		352	\\};
		353	\\
		354	);
		355	}
		356
		357	test "zig fmt: container declaration, multiline string, add trailing comma" {
		358	try testTransform(
		359	\\const X = struct {
		360	\\ foo: []const u8 =
		361	\\ \\ foo
		362	\\ ,
		363	\\ bar: i8
		364	\\};
		365	,
		366	\\const X = struct {
		367	\\ foo: []const u8 =
		368	\\ \\ foo
		369	\\ ,
		370	\\ bar: i8,
		371	\\};
		372	\\
		373	);
		374	}
		375
332	test "zig fmt: remove empty lines at start/end of container decl" {	376	test "zig fmt: remove empty lines at start/end of container decl" {
333	try testTransform(	377	try testTransform(
334	\\const X = struct {	378	\\const X = struct {

lib/std/zig/render.zig+23-5

 @@ -1206,7 +1206,7 @@ fn renderContainerField(
         ais.pushIndent();
         try renderExpression(gpa, ais, tree, field.ast.value_expr, .none); // value
         ais.popIndent();
-        try renderToken(ais, tree, maybe_comma, space);
+        try renderToken(ais, tree, maybe_comma, .newline);
     } else {
         ais.pushIndent();
         try renderExpression(gpa, ais, tree, field.ast.value_expr, space); // value
 @@ -1894,7 +1894,11 @@ fn renderContainerDecl(
     const src_has_trailing_comma = token_tags[rbrace - 1] == .comma;
     if (!src_has_trailing_comma) one_line: {
-        // We can only print all the members in-line if all the members are fields.
+        // We can only print all the members in-line if there are no comments or multiline strings,
+        // and all the members are fields.
+        if (hasComment(tree, lbrace, rbrace) or hasMultilineString(tree, lbrace, rbrace)) {
+            break :one_line;
+        }
         for (container_decl.ast.members) |member| {
             if (!node_tags[member].isContainerField()) break :one_line;
         }
 @@ -1912,7 +1916,18 @@ fn renderContainerDecl(
     if (token_tags[lbrace + 1] == .container_doc_comment) {
         try renderContainerDocComments(ais, tree, lbrace + 1);
     }
-    try renderMembers(gpa, ais, tree, container_decl.ast.members);
+    for (container_decl.ast.members) |member, i| {
+        if (i != 0) try renderExtraNewline(ais, tree, member);
+        switch (tree.nodes.items(.tag)[member]) {
+            // For container fields, ensure a trailing comma is added if necessary.
+            .container_field_init,
+            .container_field_align,
+            .container_field,
+            => try renderMember(gpa, ais, tree, member, .comma),
+            else => try renderMember(gpa, ais, tree, member, .newline),
+        }
+    }
     ais.popIndent();
     return renderToken(ais, tree, rbrace, space); // rbrace
 @@ -2200,10 +2215,11 @@ fn renderExpressionIndented(gpa: *Allocator, ais: *Ais, tree: Ast, node: Ast.Nod
 }
 /// Render an expression, and the comma that follows it, if it is present in the source.
+/// If a comma is present, and `space` is `Space.comma`, render only a single comma.
 fn renderExpressionComma(gpa: *Allocator, ais: *Ais, tree: Ast, node: Ast.Node.Index, space: Space) Error!void {
     const token_tags = tree.tokens.items(.tag);
     const maybe_comma = tree.lastToken(node) + 1;
-    if (token_tags[maybe_comma] == .comma) {
+    if (token_tags[maybe_comma] == .comma and space != .comma) {
         try renderExpression(gpa, ais, tree, node, .none);
         return renderToken(ais, tree, maybe_comma, space);
     } else {
 @@ -2211,10 +2227,12 @@ fn renderExpressionComma(gpa: *Allocator, ais: *Ais, tree: Ast, node: Ast.Node.I
     }
 }
+/// Render a token, and the comma that follows it, if it is present in the source.
+/// If a comma is present, and `space` is `Space.comma`, render only a single comma.
 fn renderTokenComma(ais: *Ais, tree: Ast, token: Ast.TokenIndex, space: Space) Error!void {
     const token_tags = tree.tokens.items(.tag);
     const maybe_comma = token + 1;
-    if (token_tags[maybe_comma] == .comma) {
+    if (token_tags[maybe_comma] == .comma and space != .comma) {
         try renderToken(ais, tree, token, .none);
         return renderToken(ais, tree, maybe_comma, space);
     } else {