Commit b4db03d8bb

Lewis Gaul <legaul@cisco.com>
2021-03-01 00:46:35
zig fmt: fix extra newline before if nested in for
Add failing testcase to reproduce issue 8088 Tidy up renderWhile(), factoring out renderWhilePayload() Ensure correct newline is used before 'then' token in while/for/if Handle indents for 'if' inside 'for' or 'while' Stop special-casing 'if' compared to 'for' and 'while'
master
1 parent a502c16
Changed files (2)
lib
std
zig
parser_test.zig
render.zig
lib/std/zig/parser_test.zig
@@ -3184,6 +3184,31 @@ test "zig fmt: for" {
     );
 }
 
+test "zig fmt: for if" {
+    try testCanonical(
+        \\test "for if" {
+        \\    for (a) |x| if (x) f(x);
+        \\
+        \\    for (a) |x| if (x)
+        \\        f(x);
+        \\
+        \\    for (a) |x| if (x) {
+        \\        f(x);
+        \\    };
+        \\
+        \\    for (a) |x|
+        \\        if (x)
+        \\            f(x);
+        \\
+        \\    for (a) |x|
+        \\        if (x) {
+        \\            f(x);
+        \\        };
+        \\}
+        \\
+    );
+}
+
 test "zig fmt: if" {
     try testCanonical(
         \\test "if" {
lib/std/zig/render.zig
@@ -1025,31 +1025,11 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
     const then_tag = node_tags[while_node.ast.then_expr];
     if (nodeIsBlock(then_tag) and !nodeIsIf(then_tag)) {
         if (while_node.payload_token) |payload_token| {
-            try renderToken(ais, tree, payload_token - 2, .space); // rparen
-            try renderToken(ais, tree, payload_token - 1, .none); // |
-            const ident = blk: {
-                if (token_tags[payload_token] == .asterisk) {
-                    try renderToken(ais, tree, payload_token, .none); // *
-                    break :blk payload_token + 1;
-                } else {
-                    break :blk payload_token;
-                }
-            };
-            try renderToken(ais, tree, ident, .none); // identifier
-            const pipe = blk: {
-                if (token_tags[ident + 1] == .comma) {
-                    try renderToken(ais, tree, ident + 1, .space); // ,
-                    try renderToken(ais, tree, ident + 2, .none); // index
-                    break :blk ident + 3;
-                } else {
-                    break :blk ident + 1;
-                }
-            };
             const brace_space = if (while_node.ast.cont_expr == 0 and ais.isLineOverIndented())
                 Space.newline
             else
                 Space.space;
-            try renderToken(ais, tree, pipe, brace_space); // |
+            try renderWhilePayload(gpa, ais, tree, payload_token, brace_space);
         } else {
             const rparen = tree.lastToken(while_node.ast.cond_expr) + 1;
             const brace_space = if (while_node.ast.cont_expr == 0 and ais.isLineOverIndented())
@@ -1082,38 +1062,23 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
     }
 
     const rparen = tree.lastToken(while_node.ast.cond_expr) + 1;
+    const first_then_token = tree.firstToken(while_node.ast.then_expr);
     const last_then_token = tree.lastToken(while_node.ast.then_expr);
     const src_has_newline = !tree.tokensOnSameLine(rparen, last_then_token);
 
     if (src_has_newline) {
+        const newline_before_then_token = !tree.tokensOnSameLine(rparen, first_then_token);
+        const space_before_then_token: Space = if (newline_before_then_token) .newline else .space;
+        const indent_expression = !nodeIsIf(then_tag) or newline_before_then_token;
+
         if (while_node.payload_token) |payload_token| {
-            try renderToken(ais, tree, payload_token - 2, .space); // rparen
-            try renderToken(ais, tree, payload_token - 1, .none); // |
-            const ident = blk: {
-                if (token_tags[payload_token] == .asterisk) {
-                    try renderToken(ais, tree, payload_token, .none); // *
-                    break :blk payload_token + 1;
-                } else {
-                    break :blk payload_token;
-                }
-            };
-            try renderToken(ais, tree, ident, .none); // identifier
-            const pipe = blk: {
-                if (token_tags[ident + 1] == .comma) {
-                    try renderToken(ais, tree, ident + 1, .space); // ,
-                    try renderToken(ais, tree, ident + 2, .none); // index
-                    break :blk ident + 3;
-                } else {
-                    break :blk ident + 1;
-                }
-            };
-            const after_space: Space = if (while_node.ast.cont_expr != 0) .space else .newline;
-            try renderToken(ais, tree, pipe, after_space); // |
+            const after_space: Space = if (while_node.ast.cont_expr != 0) .space else space_before_then_token;
+            try renderWhilePayload(gpa, ais, tree, payload_token, after_space);
         } else {
-            ais.pushIndent();
-            const after_space: Space = if (while_node.ast.cont_expr != 0) .space else .newline;
+            if (indent_expression) ais.pushIndent();
+            const after_space: Space = if (while_node.ast.cont_expr != 0) .space else space_before_then_token;
             try renderToken(ais, tree, rparen, after_space); // rparen
-            ais.popIndent();
+            if (indent_expression) ais.popIndent();
         }
         if (while_node.ast.cont_expr != 0) {
             const cont_rparen = tree.lastToken(while_node.ast.cont_expr) + 1;
@@ -1121,12 +1086,12 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
             try renderToken(ais, tree, cont_lparen - 1, .space); // :
             try renderToken(ais, tree, cont_lparen, .none); // lparen
             try renderExpression(gpa, ais, tree, while_node.ast.cont_expr, .none);
-            try renderToken(ais, tree, cont_rparen, .newline); // rparen
+            try renderToken(ais, tree, cont_rparen, space_before_then_token); // rparen
         }
         if (while_node.ast.else_expr != 0) {
-            ais.pushIndent();
-            try renderExpression(gpa, ais, tree, while_node.ast.then_expr, Space.newline);
-            ais.popIndent();
+            if (indent_expression) ais.pushIndent();
+            try renderExpression(gpa, ais, tree, while_node.ast.then_expr, .newline);
+            if (indent_expression) ais.popIndent();
             const else_is_block = nodeIsBlock(node_tags[while_node.ast.else_expr]);
             if (else_is_block) {
                 try renderToken(ais, tree, while_node.else_token, .space); // else
@@ -1145,12 +1110,18 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
                 } else {
                     try renderToken(ais, tree, while_node.else_token, .newline); // else
                 }
-                try renderExpressionIndented(gpa, ais, tree, while_node.ast.else_expr, space);
-                return;
+                if (indent_expression) {
+                    return renderExpressionIndented(gpa, ais, tree, while_node.ast.else_expr, space);
+                } else {
+                    return renderExpression(gpa, ais, tree, while_node.ast.else_expr, space);
+                }
             }
         } else {
-            try renderExpressionIndented(gpa, ais, tree, while_node.ast.then_expr, space);
-            return;
+            if (indent_expression) {
+                return renderExpressionIndented(gpa, ais, tree, while_node.ast.then_expr, space);
+            } else {
+                return renderExpression(gpa, ais, tree, while_node.ast.then_expr, space);
+            }
         }
     }
 
@@ -1158,27 +1129,7 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
 
     if (while_node.payload_token) |payload_token| {
         assert(payload_token - 2 == rparen);
-        try renderToken(ais, tree, payload_token - 2, .space); // )
-        try renderToken(ais, tree, payload_token - 1, .none); // |
-        const ident = blk: {
-            if (token_tags[payload_token] == .asterisk) {
-                try renderToken(ais, tree, payload_token, .none); // *
-                break :blk payload_token + 1;
-            } else {
-                break :blk payload_token;
-            }
-        };
-        try renderToken(ais, tree, ident, .none); // identifier
-        const pipe = blk: {
-            if (token_tags[ident + 1] == .comma) {
-                try renderToken(ais, tree, ident + 1, .space); // ,
-                try renderToken(ais, tree, ident + 2, .none); // index
-                break :blk ident + 3;
-            } else {
-                break :blk ident + 1;
-            }
-        };
-        try renderToken(ais, tree, pipe, .space); // |
+        try renderWhilePayload(gpa, ais, tree, payload_token, .space);
     } else {
         try renderToken(ais, tree, rparen, .space); // )
     }
@@ -1208,6 +1159,31 @@ fn renderWhile(gpa: *Allocator, ais: *Ais, tree: ast.Tree, while_node: ast.full.
     }
 }
 
+fn renderWhilePayload(gpa: *Allocator, ais: *Ais, tree: ast.Tree, payload_token: ast.TokenIndex, space: Space) Error!void {
+    const token_tags = tree.tokens.items(.tag);
+    try renderToken(ais, tree, payload_token - 2, .space); // rparen
+    try renderToken(ais, tree, payload_token - 1, .none); // |
+    const ident = blk: {
+        if (token_tags[payload_token] == .asterisk) {
+            try renderToken(ais, tree, payload_token, .none); // *
+            break :blk payload_token + 1;
+        } else {
+            break :blk payload_token;
+        }
+    };
+    try renderToken(ais, tree, ident, .none); // identifier
+    const pipe = blk: {
+        if (token_tags[ident + 1] == .comma) {
+            try renderToken(ais, tree, ident + 1, .space); // ,
+            try renderToken(ais, tree, ident + 2, .none); // index
+            break :blk ident + 3;
+        } else {
+            break :blk ident + 1;
+        }
+    };
+    try renderToken(ais, tree, pipe, space); // |
+}
+
 fn renderContainerField(
     gpa: *Allocator,
     ais: *Ais,