Current Dev State

static/js/ketcher2/node_modules/espree/lib/comment-attachment.js

@@ -0,0 +1,175 @@
+/**
+ * @fileoverview Attaches comments to the AST.
+ * @author Nicholas C. Zakas
+ */
+
+"use strict";
+
+//------------------------------------------------------------------------------
+// Requirements
+//------------------------------------------------------------------------------
+
+var astNodeTypes = require("./ast-node-types");
+
+//------------------------------------------------------------------------------
+// Private
+//------------------------------------------------------------------------------
+
+var extra = {
+    trailingComments: [],
+    leadingComments: [],
+    bottomRightStack: [],
+    previousNode: null
+};
+
+//------------------------------------------------------------------------------
+// Public
+//------------------------------------------------------------------------------
+
+module.exports = {
+
+    reset: function() {
+        extra.trailingComments = [];
+        extra.leadingComments = [];
+        extra.bottomRightStack = [];
+        extra.previousNode = null;
+    },
+
+    addComment: function(comment) {
+        extra.trailingComments.push(comment);
+        extra.leadingComments.push(comment);
+    },
+
+    processComment: function(node) {
+        var lastChild,
+            trailingComments,
+            i,
+            j;
+
+        if (node.type === astNodeTypes.Program) {
+            if (node.body.length > 0) {
+                return;
+            }
+        }
+
+        if (extra.trailingComments.length > 0) {
+
+            /*
+             * If the first comment in trailingComments comes after the
+             * current node, then we're good - all comments in the array will
+             * come after the node and so it's safe to add then as official
+             * trailingComments.
+             */
+            if (extra.trailingComments[0].range[0] >= node.range[1]) {
+                trailingComments = extra.trailingComments;
+                extra.trailingComments = [];
+            } else {
+
+                /*
+                 * Otherwise, if the first comment doesn't come after the
+                 * current node, that means we have a mix of leading and trailing
+                 * comments in the array and that leadingComments contains the
+                 * same items as trailingComments. Reset trailingComments to
+                 * zero items and we'll handle this by evaluating leadingComments
+                 * later.
+                 */
+                extra.trailingComments.length = 0;
+            }
+        } else {
+            if (extra.bottomRightStack.length > 0 &&
+                    extra.bottomRightStack[extra.bottomRightStack.length - 1].trailingComments &&
+                    extra.bottomRightStack[extra.bottomRightStack.length - 1].trailingComments[0].range[0] >= node.range[1]) {
+                trailingComments = extra.bottomRightStack[extra.bottomRightStack.length - 1].trailingComments;
+                delete extra.bottomRightStack[extra.bottomRightStack.length - 1].trailingComments;
+            }
+        }
+
+        // Eating the stack.
+        while (extra.bottomRightStack.length > 0 && extra.bottomRightStack[extra.bottomRightStack.length - 1].range[0] >= node.range[0]) {
+            lastChild = extra.bottomRightStack.pop();
+        }
+
+        if (lastChild) {
+            if (lastChild.leadingComments) {
+                if (lastChild.leadingComments[lastChild.leadingComments.length - 1].range[1] <= node.range[0]) {
+                    node.leadingComments = lastChild.leadingComments;
+                    delete lastChild.leadingComments;
+                } else {
+                    // A leading comment for an anonymous class had been stolen by its first MethodDefinition,
+                    // so this takes back the leading comment.
+                    // See Also: https://github.com/eslint/espree/issues/158
+                    for (i = lastChild.leadingComments.length - 2; i >= 0; --i) {
+                        if (lastChild.leadingComments[i].range[1] <= node.range[0]) {
+                            node.leadingComments = lastChild.leadingComments.splice(0, i + 1);
+                            break;
+                        }
+                    }
+                }
+            }
+        } else if (extra.leadingComments.length > 0) {
+            if (extra.leadingComments[extra.leadingComments.length - 1].range[1] <= node.range[0]) {
+                if (extra.previousNode) {
+                    for (j = 0; j < extra.leadingComments.length; j++) {
+                        if (extra.leadingComments[j].end < extra.previousNode.end) {
+                            extra.leadingComments.splice(j, 1);
+                            j--;
+                        }
+                    }
+                }
+                if (extra.leadingComments.length > 0) {
+                    node.leadingComments = extra.leadingComments;
+                    extra.leadingComments = [];
+                }
+            } else {
+
+                // https://github.com/eslint/espree/issues/2
+
+                /*
+                 * In special cases, such as return (without a value) and
+                 * debugger, all comments will end up as leadingComments and
+                 * will otherwise be eliminated. This extra step runs when the
+                 * bottomRightStack is empty and there are comments left
+                 * in leadingComments.
+                 *
+                 * This loop figures out the stopping point between the actual
+                 * leading and trailing comments by finding the location of the
+                 * first comment that comes after the given node.
+                 */
+                for (i = 0; i < extra.leadingComments.length; i++) {
+                    if (extra.leadingComments[i].range[1] > node.range[0]) {
+                        break;
+                    }
+                }
+
+                /*
+                 * Split the array based on the location of the first comment
+                 * that comes after the node. Keep in mind that this could
+                 * result in an empty array, and if so, the array must be
+                 * deleted.
+                 */
+                node.leadingComments = extra.leadingComments.slice(0, i);
+                if (node.leadingComments.length === 0) {
+                    delete node.leadingComments;
+                }
+
+                /*
+                 * Similarly, trailing comments are attached later. The variable
+                 * must be reset to null if there are no trailing comments.
+                 */
+                trailingComments = extra.leadingComments.slice(i);
+                if (trailingComments.length === 0) {
+                    trailingComments = null;
+                }
+            }
+        }
+
+        extra.previousNode = node;
+
+        if (trailingComments) {
+            node.trailingComments = trailingComments;
+        }
+
+        extra.bottomRightStack.push(node);
+    }
+
+};