Fix isFirstNested util to handle shared-line comments

lib/rules/at-rule-empty-line-before/__tests__/index.js

@@ -345,6 +345,10 @@ testRule(
     accept: [
       {
         code: "a {\n  @mixin foo;\n  color: pink;\n}"
+      },
+      {
+        code: "a { /* comment */\n  @mixin foo;\n  color: pink;\n}",
+        description: "shared-line comment"
       }
     ],
 
@@ -358,6 +362,11 @@ testRule(
         code: "a {\n\n  @mixin foo;\n  color: pink;\n}",
         fixed: "a {\n  @mixin foo;\n  color: pink;\n}",
         message: messages.rejected
+      },
+      {
+        code: "a {/* comment */\n\n  @mixin foo;\n  color: pink;\n}",
+        fixed: "a {/* comment */\n  @mixin foo;\n  color: pink;\n}",
+        message: messages.rejected
       }
     ]
   })

lib/rules/comment-empty-line-before/__tests__/index.js

@@ -103,6 +103,12 @@ testRule(
       {
         code: "a {\n  /* comment */\n  color: pink;\n}",
         description: "first-nested without empty line before"
+      },
+      {
+        code:
+          "a { /* shared-line comment */\n  /* comment */\n  color: pink;\n}",
+        description:
+          "first-nested without empty line before and shared-line comment"
       }
     ],
 
@@ -114,6 +120,16 @@ testRule(
         message: messages.rejected,
         line: 3,
         column: 3
+      },
+      {
+        code:
+          "a { /* shared-line comment */\n\n  /* comment */\n  color: pink;\n}",
+        fixed:
+          "a { /* shared-line comment */\n  /* comment */\n  color: pink;\n}",
+        description: "first-nested with empty line before",
+        message: messages.rejected,
+        line: 3,
+        column: 3
       }
     ]
   })

lib/rules/custom-property-empty-line-before/__tests__/index.js

@@ -171,6 +171,10 @@ testRule(rule, {
     },
     {
       code: "a {\r\n --custom-prop: value;\r\n}"
+    },
+    {
+      code: "a { /* comment */\n --custom-prop: value;\n}",
+      description: "shared-line comment"
     }
   ],
 
@@ -188,6 +192,13 @@ testRule(rule, {
       message: messages.rejected,
       line: 3,
       column: 2
+    },
+    {
+      code: "a { /* comment*/\n\n --custom-prop: value;\n}",
+      fixed: "a { /* comment*/\n --custom-prop: value;\n}",
+      message: messages.rejected,
+      line: 3,
+      column: 2
     }
   ]
 });

lib/rules/declaration-empty-line-before/__tests__/index.js

@@ -365,6 +365,10 @@ testRule(rule, {
     },
     {
       code: "a {\r\n top: 15px;\r\n}"
+    },
+    {
+      code: "a { /* comment */\n top: 15px;\n}",
+      description: "shared-line comment"
     }
   ],
 
@@ -382,6 +386,13 @@ testRule(rule, {
       message: messages.rejected,
       line: 3,
       column: 2
+    },
+    {
+      code: "a { /* comment */\n\n top: 15px;\n}",
+      fixed: "a { /* comment */\n top: 15px;\n}",
+      message: messages.rejected,
+      line: 3,
+      column: 2
     }
   ]
 });

lib/rules/rule-empty-line-before/__tests__/index.js

@@ -235,6 +235,10 @@ testRule(rule, {
       code: "@media {\r\n  a {}\r\n\r\n}",
       description: "CRLF"
     },
+    {
+      code: "@media { /* comment */\n  a {}\n\n}",
+      description: "shared-line comment boog"
+    },
     {
       code: "@media {\n  a {}\n\n  b{}\n\n}"
     },
@@ -268,6 +272,16 @@ testRule(rule, {
       fixed: "@media {\n  a {}\n}",
       message: messages.rejected
     },
+    {
+      code: "@media { /* comment */\n\n  a {}\n}",
+      fixed: "@media { /* comment */\n  a {}\n}",
+      message: messages.rejected
+    },
+    {
+      code: "@media { /* comment */\n\n  a {}\n}",
+      fixed: "@media { /* comment */\n  a {}\n}",
+      message: messages.rejected
+    },
     {
       code: "@media {\n\n  a {}\n\n  b{}\n}",
       fixed: "@media {\n  a {}\n\n  b{}\n}",

lib/rules/rule-empty-line-before/index.js

@@ -2,6 +2,7 @@
 
 const addEmptyLineBefore = require("../../utils/addEmptyLineBefore");
 const hasEmptyLine = require("../../utils/hasEmptyLine");
+const isFirstNested = require("../../utils/isFirstNested");
 const isSingleLineString = require("../../utils/isSingleLineString");
 const isStandardSyntaxRule = require("../../utils/isStandardSyntaxRule");
 const optionsMatches = require("../../utils/optionsMatches");
@@ -86,7 +87,7 @@ const rule = function(expectation, options, context) {
       // Optionally reverse the expectation for the first nested node
       if (
         optionsMatches(options, "except", "first-nested") &&
-        rule === rule.parent.first
+        isFirstNested(rule)
       ) {
         expectEmptyLineBefore = !expectEmptyLineBefore;
       }

lib/utils/__tests__/isFirstNested.test.js

@@ -17,6 +17,9 @@ describe("isFirstNested", () => {
       @media (min-width: 0px) {
         a { color: 'pink'; }
       }
+      @media (min-width: 0px) { /* comment */
+        a { color: 'pink'; }
+      }
     `);
 
     root.walkRules(rule => {
@@ -29,18 +32,39 @@ describe("isFirstNested", () => {
       a {
         @include foo;
       }
+      b { /* comment */
+        @include foo;
+      }
     `);
 
     root.walkAtRules(atRule => {
       expect(isFirstNested(atRule)).toBe(true);
     });
   });
 
+  it("returns true with the first-nested declaration", () => {
+    const root = postcss.parse(`
+      a {
+        color: pink;
+      }
+      b { /* comment */
+        color: pink;
+      }
+    `);
+
+    root.walkDecls(atRule => {
+      expect(isFirstNested(atRule)).toBe(true);
+    });
+  });
+
   it("returns true with first-nested non-statement", () => {
     const root = postcss.parse(`
       a {
         /* comment */
       }
+      b { /* shared-line comment */
+        /* comment */
+      }
     `);
 
     root.walkComments(comment => {
@@ -54,6 +78,10 @@ describe("isFirstNested", () => {
         a { color: 'pink'; }
         b { color: 'pink'; }
       }
+      @media (min-width: 0px) {
+        /* comment */
+        b { color: 'pink'; }
+      }
     `);
 
     root.walkRules("b", rule => {
@@ -67,10 +95,39 @@ describe("isFirstNested", () => {
         @include foo;
         @expect bar;
       }
+      b {
+        /* comment */
+        @expect bar;
+      }
     `);
 
     root.walkAtRules("expect", atRule => {
       expect(isFirstNested(atRule)).toBe(false);
     });
   });
+
+  it("returns false with not-first-nested declaration", () => {
+    const root = postcss.parse(`
+      a {
+        font-size: 0;
+        color: pink;
+      }
+      b {
+        /* comment */
+        color: pink;
+      }
+      c { /* comment */ /* comment */
+        /* comment */
+        color: pink;
+      }
+      d { /* shared-line/multi-line
+             comment */
+        color: pink;
+      }
+    `);
+
+    root.walkDecls("color", atRule => {
+      expect(isFirstNested(atRule)).toBe(false);
+    });
+  });
 });

lib/utils/isFirstNested.js

@@ -4,9 +4,41 @@
 module.exports = function(statement /*: postcss$node*/) /*: boolean*/ {
   const parentNode = statement.parent;
 
-  return (
-    parentNode !== undefined &&
-    parentNode.type !== "root" &&
-    statement === parentNode.first
-  );
+  if (parentNode === undefined || parentNode.type === "root") {
+    return false;
+  }
+
+  if (statement === parentNode.first) {
+    return true;
+  }
+
+  /*
+   * Search for the statement in the parent's nodes, ignoring comment
+   * nodes on the same line as the parent's opening brace.
+   */
+
+  const parentNodes = parentNode.nodes;
+  const firstNode = parentNodes[0];
+
+  if (firstNode.type !== "comment" || firstNode.raws.before.includes("\n")) {
+    return false;
+  }
+
+  const openingBraceLine = firstNode.source.start.line;
+
+  if (openingBraceLine !== firstNode.source.end.line) {
+    return false;
+  }
+
+  for (let i = 1; i < parentNodes.length; i++) {
+    const node = parentNodes[i];
+
+    if (node === statement) {
+      return true;
+    }
+
+    if (node.type !== "comment" || node.source.end.line !== openingBraceLine) {
+      return false;
+    }
+  }
 };