From 6be90dc3728ee50969c6d94728b02d29ae90c590 Mon Sep 17 00:00:00 2001
From: Wagner Maciel <wagnermaciel@google.com>
Date: Wed, 2 Nov 2022 12:02:32 -0400
Subject: [PATCH] fix(material/schematics): add binding parsing logic

---
 .../components/slider/slider-template.ts      | 90 +++++++++++++++++++
 1 file changed, 90 insertions(+)

diff --git a/src/material/schematics/ng-generate/mdc-migration/rules/components/slider/slider-template.ts b/src/material/schematics/ng-generate/mdc-migration/rules/components/slider/slider-template.ts
index 73f9013f0c56..969478a4373f 100644
--- a/src/material/schematics/ng-generate/mdc-migration/rules/components/slider/slider-template.ts
+++ b/src/material/schematics/ng-generate/mdc-migration/rules/components/slider/slider-template.ts
@@ -11,12 +11,34 @@ import {TemplateMigrator} from '../../template-migrator';
 import {visitElements} from '../../tree-traversal';
 import {Update} from '../../../../../migration-utilities';
 
+/** Contains a parsed binding node's standardized data. */
+interface Binding {
+  /** The actual compiler ast binding node. */
+  node: compiler.TmplAstNode;
+  /** The type of binding this node is. */
+  type: BindingType;
+  /** The name of the property, attribute, or event. */
+  name: string;
+  /** The event handler or property/attribute value. */
+  value: string;
+}
+
+/** Describes the different types of bindings we care about. */
+const enum BindingType {
+  INPUT,
+  OUTPUT,
+  ATTRIBUTE,
+  TWO_WAY_BINDING,
+}
+
 export class SliderTemplateMigrator extends TemplateMigrator {
   getUpdates(ast: compiler.ParsedTemplate): Update[] {
     const updates: Update[] = [];
 
     visitElements(ast.nodes, (node: compiler.TmplAstElement) => {
       if (node.name === 'mat-slider') {
+        this._getBindings(node);
+
         updates.push({
           offset: node.sourceSpan.start.offset,
           updateFn: (html: string) => html,
@@ -25,4 +47,72 @@ export class SliderTemplateMigrator extends TemplateMigrator {
     });
     return updates;
   }
+
+  /** Returns all of the property, attribute, event, or two-way bindings on the given node. */
+  private _getBindings(node: compiler.TmplAstElement): Binding[] {
+    const allInputs = this._getInputs(node);
+    const allOutputs = this._getOutputs(node);
+    const attributes = this._getAttributes(node);
+    const twoWayBindings = this._getTwoWayBindings(allInputs, allOutputs);
+
+    // Remove the inputs & outputs that are two-way bindings.
+
+    const inputs = allInputs.filter(
+      input => !twoWayBindings.some(binding => binding.name === input.name),
+    );
+    const outputs = allOutputs.filter(
+      output => !twoWayBindings.some(binding => binding.name === output.name),
+    );
+
+    return inputs.concat(outputs).concat(attributes).concat(twoWayBindings);
+  }
+
+  /** Returns the two-way bindings based on the given input & output bindings. */
+  private _getTwoWayBindings(inputs: Binding[], outputs: Binding[]): Binding[] {
+    return inputs
+      .filter(input => outputs.some(output => output.name === input.name))
+      .map(input => ({...input, type: BindingType.TWO_WAY_BINDING}));
+  }
+
+  /** Returns the output bindings on the given node. */
+  private _getOutputs(node: compiler.TmplAstElement): Binding[] {
+    return node.outputs.map(output => ({
+      node: output,
+      type: BindingType.OUTPUT,
+      name: node.sourceSpan.start.file.content.slice(
+        output.keySpan.start.offset,
+        output.keySpan.end.offset,
+      ),
+      value: node.sourceSpan.start.file.content.slice(
+        output.handlerSpan.start.offset,
+        output.handlerSpan.end.offset,
+      ),
+    }));
+  }
+
+  /** Returns the input bindings on the given node. */
+  private _getInputs(node: compiler.TmplAstElement): Binding[] {
+    return node.inputs.map(input => ({
+      node: input,
+      type: BindingType.INPUT,
+      name: node.sourceSpan.start.file.content.slice(
+        input.keySpan.start.offset,
+        input.keySpan.end.offset,
+      ),
+      value: node.sourceSpan.start.file.content.slice(
+        input.value.sourceSpan.start,
+        input.value.sourceSpan.end,
+      ),
+    }));
+  }
+
+  /** Returns the attributes on the given node. */
+  private _getAttributes(node: compiler.TmplAstElement): Binding[] {
+    return node.attributes.map(attribute => ({
+      node: attribute,
+      type: BindingType.ATTRIBUTE,
+      name: attribute.name,
+      value: attribute.value,
+    }));
+  }
 }