API for getting the node at specific source location.

API.md

@@ -287,6 +287,17 @@ String(cloned);
 // => #search
 ```
 
+### `node.isAtPosition(line, column)`
+
+Return a `boolean` indicating whether this node includes the character at the
+position of the given line and column. Returns `undefined` if the nodes lack
+sufficient source metadata to determine the position.
+
+Arguments:
+
+* `line`: 1-index based line number relative to the start of the selector.
+* `column`: 1-index based column number relative to the start of the selector.
+
 ### `node.spaces`
 
 Extra whitespaces around the node will be moved into `node.spaces.before` and
@@ -381,6 +392,19 @@ Arguments:
 
 * `index`: The index of the node to return.
 
+### `container.atPosition(line, column)`
+
+Returns the node at the source position `index`.
+
+```js
+selector.at(0) === selector.first;
+selector.at(0) === selector.nodes[0];
+```
+
+Arguments:
+
+* `index`: The index of the node to return.
+
 ### `container.index(node)`
 
 Return the index of the node within its container.

postcss-selector-parser.d.ts

@@ -164,6 +164,13 @@ declare namespace parser {
         next(): Node;
         prev(): Node;
         clone(opts: {[override: string]:any}): Node;
+        /**
+         * Return whether this node includes the character at the position of the given line and column.
+         * Returns undefined if the nodes lack sufficient source metadata to determine the position.
+         * @param line 1-index based line number relative to the start of the selector.
+         * @param column 1-index based column number relative to the start of the selector.
+         */
+        isAtPosition(line: number, column: number): boolean | undefined;
         /**
          * Some non-standard syntax doesn't follow normal escaping rules for css,
          * this allows the escaped value to be specified directly, allowing illegal characters to be
@@ -201,6 +208,20 @@ declare namespace parser {
         append(selector: Selector): Container;
         prepend(selector: Selector): Container;
         at(index: number): Node;
+        /**
+         * Return the most specific node at the line and column number given.
+         * The source location is based on the original parsed location, locations aren't
+         * updated as selector nodes are mutated.
+         *
+         * Note that this location is relative to the location of the first character
+         * of the selector, and not the location of the selector in the overall document
+         * when used in conjunction with postcss.
+         *
+         * If not found, returns undefined.
+         * @param line The line number of the node to find. (1-based index)
+         * @param col  The column number of the node to find. (1-based index)
+         */
+        atPosition(line: number, column: number): Node;
         index(child: Node): number;
         readonly first: Node;
         readonly last: Node;
@@ -259,6 +280,7 @@ declare namespace parser {
          * a postcss Rule node, a better error message is raised.
          */
         error(message: string, options?: ErrorOptions): Error;
+        nodeAt(line: number, column: number): Node
     }
     function root(opts: ContainerOptions): Root;
     function isRoot(node: any): node is Root;

src/__tests__/comments.js

@@ -5,6 +5,24 @@ test('comments', '/*test comment*/h2', (t, tree) => {
     t.deepEqual(tree.nodes[0].nodes[1].value, 'h2');
 });
 
+test('comments', '.a  /*test comment*/label', (t, tree) => {
+    t.deepEqual(tree.nodes[0].nodes[0].type, 'class');
+    t.deepEqual(tree.nodes[0].nodes[1].type, 'combinator');
+    t.deepEqual(tree.nodes[0].nodes[1].value, ' ');
+    t.deepEqual(tree.nodes[0].nodes[1].spaces.after, ' ');
+    t.deepEqual(tree.nodes[0].nodes[1].rawSpaceAfter, ' /*test comment*/');
+    t.deepEqual(tree.nodes[0].nodes[2].type, 'tag');
+});
+
+test('comments', '.a  /*test comment*/  label', (t, tree) => {
+    t.deepEqual(tree.nodes[0].nodes[0].type, 'class');
+    t.deepEqual(tree.nodes[0].nodes[1].type, 'combinator');
+    t.deepEqual(tree.nodes[0].nodes[1].value, ' ');
+    t.deepEqual(tree.nodes[0].nodes[1].spaces.before, '   ');
+    t.deepEqual(tree.nodes[0].nodes[1].rawSpaceBefore, '  /*test comment*/ ');
+    t.deepEqual(tree.nodes[0].nodes[2].type, 'tag');
+});
+
 test('multiple comments and other things', 'h1/*test*/h2/*test*/.test/*test*/', (t, tree) => {
     t.deepEqual(tree.nodes[0].nodes[0].type, 'tag', 'should have a tag');
     t.deepEqual(tree.nodes[0].nodes[1].type, 'comment', 'should have a comment');

src/__tests__/container.js

@@ -349,3 +349,55 @@ test('container#insertAfter (during iteration)', (t) => {
     });
     t.deepEqual(out, 'h1[class], h2[class], h3[class]');
 });
+
+test('Container#atPosition first pseudo', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(1, 1);
+        t.deepEqual(node.type, "pseudo");
+        t.deepEqual(node.toString(), ":not(.foo)");
+    });
+});
+
+test('Container#atPosition class in pseudo', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(1, 6);
+        t.deepEqual(node.type, "class");
+        t.deepEqual(node.toString(), ".foo");
+    });
+});
+
+test('Container#atPosition id in second selector', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(2, 1);
+        t.deepEqual(node.type, "id");
+        t.deepEqual(node.toString(), "\n#foo");
+    });
+});
+
+test('Container#atPosition combinator in second selector', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(2, 6);
+        t.deepEqual(node.type, "combinator");
+        t.deepEqual(node.toString(), " > ");
+
+        let nodeSpace = root.atPosition(2, 5);
+        t.deepEqual(nodeSpace.type, "selector");
+        t.deepEqual(nodeSpace.toString(), "\n#foo > :matches(ol, ul)");
+    });
+});
+
+test('Container#atPosition tag in second selector pseudo', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(2, 17);
+        t.deepEqual(node.type, "tag");
+        t.deepEqual(node.toString(), "ol");
+    });
+});
+
+test('Container#atPosition comma in second selector pseudo', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        let node = root.atPosition(2, 19);
+        t.deepEqual(node.type, "pseudo");
+        t.deepEqual(node.toString(), ":matches(ol, ul)");
+    });
+});

src/__tests__/node.js

@@ -80,3 +80,43 @@ test('Node#setPropertyWithoutEscape without existing raws', (t) => {
     });
     t.deepEqual(out, '.w+t+f');
 });
+
+test('Node#isAtPosition', (t) => {
+    parse(':not(.foo),\n#foo > :matches(ol, ul)', (root) => {
+        t.deepEqual(root.isAtPosition(1, 1), true);
+        t.deepEqual(root.isAtPosition(1, 10), true);
+        t.deepEqual(root.isAtPosition(2, 23), true);
+        t.deepEqual(root.isAtPosition(2, 24), false);
+        let selector = root.first;
+        t.deepEqual(selector.isAtPosition(1, 1), true);
+        t.deepEqual(selector.isAtPosition(1, 10), true);
+        t.deepEqual(selector.isAtPosition(1, 11), false);
+        let pseudoNot = selector.first;
+        t.deepEqual(pseudoNot.isAtPosition(1, 1), true);
+        t.deepEqual(pseudoNot.isAtPosition(1, 7), true);
+        t.deepEqual(pseudoNot.isAtPosition(1, 10), true);
+        t.deepEqual(pseudoNot.isAtPosition(1, 11), false);
+        let notSelector = pseudoNot.first;
+        t.deepEqual(notSelector.isAtPosition(1, 1), false);
+        t.deepEqual(notSelector.isAtPosition(1, 4), false);
+        t.deepEqual(notSelector.isAtPosition(1, 5), true);
+        t.deepEqual(notSelector.isAtPosition(1, 6), true);
+        t.deepEqual(notSelector.isAtPosition(1, 9), true);
+        t.deepEqual(notSelector.isAtPosition(1, 10), true);
+        t.deepEqual(notSelector.isAtPosition(1, 11), false);
+        let notClass = notSelector.first;
+        t.deepEqual(notClass.isAtPosition(1, 5), false);
+        t.deepEqual(notClass.isAtPosition(1, 6), true);
+        t.deepEqual(notClass.isAtPosition(1, 9), true);
+        t.deepEqual(notClass.isAtPosition(1, 10), false);
+        let secondSel = root.at(1);
+        t.deepEqual(secondSel.isAtPosition(1, 11), false);
+        t.deepEqual(secondSel.isAtPosition(2, 1), true);
+        t.deepEqual(secondSel.isAtPosition(2, 23), true);
+        t.deepEqual(secondSel.isAtPosition(2, 24), false);
+        let combinator = secondSel.at(1);
+        t.deepEqual(combinator.isAtPosition(2, 5), false);
+        t.deepEqual(combinator.isAtPosition(2, 6), true);
+        t.deepEqual(combinator.isAtPosition(2, 7), false);
+    });
+});

src/__tests__/sourceIndex.js

@@ -6,16 +6,16 @@ test('universal selector', '*', (t, tree) => {
     t.deepEqual(tree.nodes[0].nodes[0].sourceIndex, 0);
 });
 
-test('lobotomized owl selector', '* + *', (t, tree) => {
-    t.deepEqual(tree.nodes[0].nodes[0].source.start.column, 1);
-    t.deepEqual(tree.nodes[0].nodes[0].source.end.column, 1);
-    t.deepEqual(tree.nodes[0].nodes[0].sourceIndex, 0);
-    t.deepEqual(tree.nodes[0].nodes[1].source.start.column, 3);
-    t.deepEqual(tree.nodes[0].nodes[1].source.end.column, 3);
-    t.deepEqual(tree.nodes[0].nodes[1].sourceIndex, 2);
-    t.deepEqual(tree.nodes[0].nodes[2].source.start.column, 5);
-    t.deepEqual(tree.nodes[0].nodes[2].source.end.column, 5);
-    t.deepEqual(tree.nodes[0].nodes[2].sourceIndex, 4);
+test('lobotomized owl selector', ' * + * ', (t, tree) => {
+    t.deepEqual(tree.nodes[0].nodes[0].source.start.column, 2);
+    t.deepEqual(tree.nodes[0].nodes[0].source.end.column, 2);
+    t.deepEqual(tree.nodes[0].nodes[0].sourceIndex, 1);
+    t.deepEqual(tree.nodes[0].nodes[1].source.start.column, 4);
+    t.deepEqual(tree.nodes[0].nodes[1].source.end.column, 4);
+    t.deepEqual(tree.nodes[0].nodes[1].sourceIndex, 3);
+    t.deepEqual(tree.nodes[0].nodes[2].source.start.column, 6);
+    t.deepEqual(tree.nodes[0].nodes[2].source.end.column, 6);
+    t.deepEqual(tree.nodes[0].nodes[2].sourceIndex, 5);
 });
 
 test('comment', '/**\n * Hello!\n */', (t, tree) => {
@@ -184,7 +184,7 @@ test('combinators surrounded by superfluous spaces', 'div   >  h1 ~   span   a',
 
     t.deepEqual(tree.nodes[0].nodes[5].source.start.line, 1, "' ' start line");
     t.deepEqual(tree.nodes[0].nodes[5].source.start.column, 21, "' ' start column");
-    t.deepEqual(tree.nodes[0].nodes[5].source.end.column, 21, "' ' end column");
+    t.deepEqual(tree.nodes[0].nodes[5].source.end.column, 23, "' ' end column");
     t.deepEqual(tree.nodes[0].nodes[5].sourceIndex, 20, "' ' sourceIndex");
 });