refactor(compiler): Initial support for i18n attributes

Add support for i18n attributes:
- Generate i18n contexts from i18n attributes, and extract the eventual messages into the constant pool.
- Emit I18nAttributes config instructions when needed.
- Use the generated i18n variable in the appropriate places, including extracted attribute instructions, as well as I18nAttributes config arrays.

packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_i18n/element_attributes/TEST_CASES.json

@@ -145,10 +145,16 @@
           "extraChecks": [
             "verifyPlaceholdersIntegrity",
             "verifyUniqueConsts"
+          ],
+          "files": [
+            {
+              "expected": "interpolation_basic_template.js",
+              "templatePipelineExpected": "interpolation_basic_template.pipeline.js",
+              "generated": "interpolation_basic.js"
+            }
           ]
         }
-      ],
-      "skipForTemplatePipeline": true
+      ]
     },
     {
       "description": "should support interpolation with custom interpolation config",
@@ -190,25 +196,16 @@
           "extraChecks": [
             "verifyPlaceholdersIntegrity",
             "verifyUniqueConsts"
+          ],
+          "files": [
+            {
+              "expected": "interpolation_complex_expressions_template.js",
+              "templatePipelineExpected": "interpolation_complex_expressions_template.pipeline.js",
+              "generated": "interpolation_complex_expressions.js"
+            }
           ]
         }
-      ],
-      "skipForTemplatePipeline": true
-    },
-    {
-      "description": "should support complex expressions in interpolation",
-      "inputFiles": [
-        "interpolation_complex_expressions.ts"
-      ],
-      "expectations": [
-        {
-          "extraChecks": [
-            "verifyPlaceholdersIntegrity",
-            "verifyUniqueConsts"
-          ]
-        }
-      ],
-      "skipForTemplatePipeline": true
+      ]
     },
     {
       "description": "should work correctly when placed on i18n root node",

packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_i18n/element_attributes/interpolation_basic_template.pipeline.js

@@ -0,0 +1,34 @@
+decls: 5,
+vars: 8,
+consts: () => {
+  __i18nMsg__('static text', [], {}, {})
+  __i18nMsg__('intro {$interpolation}', [['interpolation', String.raw`\uFFFD0\uFFFD`]], {original_code: {'interpolation': '{{ valueA | uppercase }}'}}, {meaning: 'm', desc: 'd'})
+  __i18nMsg__('{$interpolation}', [['interpolation', String.raw`\uFFFD0\uFFFD`]], {original_code: {'interpolation': '{{ valueB }}'}}, {meaning: 'm1', desc: 'd1'})
+  __i18nMsg__('{$interpolation} and {$interpolation_1} and again {$interpolation_2}', [['interpolation', String.raw`\uFFFD0\uFFFD`],['interpolation_1', String.raw`\uFFFD1\uFFFD`],['interpolation_2', String.raw`\uFFFD2\uFFFD`]], {original_code: {'interpolation': '{{ valueA }}', 'interpolation_1': '{{ valueB }}', 'interpolation_2': '{{ valueA + valueB }}'}}, {meaning: 'm2', desc: 'd2'})
+  __i18nMsg__('{$interpolation}', [['interpolation', String.raw`\uFFFD0\uFFFD`]], {original_code: {'interpolation': '{{ valueC }}'}}, {})
+return [
+	["title", $i18n_1$, "aria-label", $i18n_2$],
+	["title", $i18n_3$, "aria-roledescription", $i18n_4$],
+    ["id", "dynamic-1", "aria-roledescription",  $i18n_0$, __AttributeMarker.I18n__,
+      "title", "aria-label"],
+    ["id", "dynamic-2", __AttributeMarker.I18n__, "title", "aria-roledescription"]
+  ];
+},
+template: function MyComponent_Template(rf, ctx) {
+  if (rf & 1) {
+    $r3$.ɵɵelementStart(0, "div", 2);
+    $r3$.ɵɵpipe(1, "uppercase");
+    $r3$.ɵɵi18nAttributes(2, 0);
+    $r3$.ɵɵelementEnd();
+    $r3$.ɵɵelementStart(3, "div", 3);
+    $r3$.ɵɵi18nAttributes(4, 1);
+    $r3$.ɵɵelementEnd();
+  }
+  if (rf & 2) {
+    $r3$.ɵɵi18nExp($r3$.ɵɵpipeBind1(1, 6, ctx.valueA))(ctx.valueB);
+    $r3$.ɵɵi18nApply(2);
+    $r3$.ɵɵadvance(3);
+    $r3$.ɵɵi18nExp(ctx.valueA)(ctx.valueB)(ctx.valueA + ctx.valueB)(ctx.valueC);
+    $r3$.ɵɵi18nApply(4);
+  }
+}

packages/compiler-cli/test/compliance/test_cases/r3_view_compiler_i18n/element_attributes/interpolation_complex_expressions_template.pipeline.js

@@ -0,0 +1,21 @@
+decls: 2,
+vars: 1,
+consts: () => {
+  __i18nMsg__('{$interpolation} title', [['interpolation', String.raw`\uFFFD0\uFFFD`]], {original_code: {'interpolation': '{{valueA.getRawValue()?.getTitle()}}'}}, {})
+  return [
+	["title", $i18n_0$],
+    [__AttributeMarker.I18n__, "title"]
+  ];
+},
+template: function MyComponent_Template(rf, ctx) {
+  if (rf & 1) {
+    $r3$.ɵɵelementStart(0, "div", 1);
+    $r3$.ɵɵi18nAttributes(1, 0);
+    $r3$.ɵɵelementEnd();
+  }
+  if (rf & 2) {
+    let $tmp_0_0$;
+    $r3$.ɵɵi18nExp(($tmp_0_0$ = ctx.valueA.getRawValue()) == null ? null : $tmp_0_0$.getTitle());
+    $r3$.ɵɵi18nApply(1);
+  }
+}

packages/compiler/src/template/pipeline/ir/src/enums.ts

@@ -234,6 +234,11 @@ export enum OpKind {
    * An i18n context containing information needed to generate an i18n message.
    */
   I18nContext,
+
+  /**
+   * A creation op that corresponds to i18n attributes on an element.
+   */
+  I18nAttributes,
 }
 
 /**
@@ -490,6 +495,21 @@ export enum I18nParamResolutionTime {
   Postproccessing
 }
 
+/**
+ * The contexts in which an i18n expression can be used.
+ */
+export enum I18nExpressionContext {
+  /**
+   * This expression is used as a value (i.e. inside an i18n block).
+   */
+  Normal,
+
+  /**
+   * This expression is used in a binding.
+   */
+  Binding,
+}
+
 /**
  * Flags that describe what an i18n param value. These determine how the value is serialized into
  * the final map.
@@ -559,7 +579,8 @@ export enum DerivedRepeaterVarIdentity {
  */
 export enum I18nContextKind {
   RootI18n,
-  Icu
+  Icu,
+  Attr
 }
 
 export enum TemplateKind {

packages/compiler/src/template/pipeline/ir/src/expression.ts

@@ -1022,6 +1022,7 @@ export function transformExpressionsInOp(
     case OpKind.ProjectionDef:
     case OpKind.Template:
     case OpKind.Text:
+    case OpKind.I18nAttributes:
       // These operations contain no expressions.
       break;
     default:

packages/compiler/src/template/pipeline/ir/src/ops/create.ts

@@ -26,7 +26,7 @@ export type CreateOp = ListEndOp<CreateOp>|StatementOp<CreateOp>|ElementOp|Eleme
     ElementEndOp|ContainerOp|ContainerStartOp|ContainerEndOp|TemplateOp|EnableBindingsOp|
     DisableBindingsOp|TextOp|ListenerOp|PipeOp|VariableOp<CreateOp>|NamespaceOp|ProjectionDefOp|
     ProjectionOp|ExtractedAttributeOp|DeferOp|DeferOnOp|RepeaterCreateOp|I18nMessageOp|I18nOp|
-    I18nStartOp|I18nEndOp|IcuStartOp|IcuEndOp|I18nContextOp;
+    I18nStartOp|I18nEndOp|IcuStartOp|IcuEndOp|I18nContextOp|I18nAttributesOp;
 
 /**
  * An operation representing the creation of an element or container.
@@ -636,20 +636,27 @@ export interface ExtractedAttributeOp extends Op<CreateOp> {
    * The value expression of the extracted attribute.
    */
   expression: o.Expression|null;
+
+  /**
+   * If this attribute has a corresponding i18n attribute (e.g. `i18n-foo="m:d"`), then this is the
+   * i18n context for it.
+   */
+  i18nContext: XrefId|null;
 }
 
 /**
  * Create an `ExtractedAttributeOp`.
  */
 export function createExtractedAttributeOp(
-    target: XrefId, bindingKind: BindingKind, name: string,
-    expression: o.Expression|null): ExtractedAttributeOp {
+    target: XrefId, bindingKind: BindingKind, name: string, expression: o.Expression|null,
+    i18nContext: XrefId|null): ExtractedAttributeOp {
   return {
     kind: OpKind.ExtractedAttribute,
     target,
     bindingKind,
     name,
     expression,
+    i18nContext,
     ...NEW_OP,
   };
 }
@@ -861,10 +868,19 @@ export interface I18nMessageOp extends Op<CreateOp> {
    */
   xref: XrefId;
 
+  /**
+   * The context from which this message was extracted
+   * TODO: remove this, and add another property here instead to match ExtractedAttributes
+   */
+  i18nContext: XrefId;
+
   /**
    * A reference to the i18n op this message was extracted from.
+   *
+   * This might be null, which means this message is not associated with a block. This probably
+   * means it is an i18n attribute's message.
    */
-  i18nBlock: XrefId;
+  i18nBlock: XrefId|null;
 
   /**
    * The i18n message represented by this op.
@@ -902,12 +918,13 @@ export interface I18nMessageOp extends Op<CreateOp> {
  * Create an `ExtractedMessageOp`.
  */
 export function createI18nMessageOp(
-    xref: XrefId, i18nBlock: XrefId, message: i18n.Message, messagePlaceholder: string|null,
-    params: Map<string, o.Expression>, postprocessingParams: Map<string, o.Expression>,
-    needsPostprocessing: boolean): I18nMessageOp {
+    xref: XrefId, i18nContext: XrefId, i18nBlock: XrefId|null, message: i18n.Message,
+    messagePlaceholder: string|null, params: Map<string, o.Expression>,
+    postprocessingParams: Map<string, o.Expression>, needsPostprocessing: boolean): I18nMessageOp {
   return {
     kind: OpKind.I18nMessage,
     xref,
+    i18nContext,
     i18nBlock,
     message,
     messagePlaceholder,
@@ -1080,13 +1097,14 @@ export function createIcuEndOp(xref: XrefId): IcuEndOp {
 
 /**
  * An i18n context that is used to generate a translated i18n message. A separate context is created
- * for two different scenarios:
+ * for three different scenarios:
  *
  * 1. For each top-level i18n block.
  * 2. For each ICU referenced as a sub-message. ICUs that are referenced as a sub-message will be
  *    used to generate a separate i18n message, but will not be extracted directly into the consts
  *    array. Instead they will be pulled in as part of the initialization statements for the message
  *    that references them.
+ * 3. For each i18n attribute.
  *
  * Child i18n blocks, resulting from the use of an ng-template inside of a parent i18n block, do not
  * generate a separate context. Instead their content is included in the translated message for
@@ -1098,7 +1116,7 @@ export interface I18nContextOp extends Op<CreateOp> {
   contextKind: I18nContextKind;
 
   /**
-   *  The id of this context.
+   * The id of this context.
    */
   xref: XrefId;
 
@@ -1107,8 +1125,11 @@ export interface I18nContextOp extends Op<CreateOp> {
    *
    * It is possible for multiple contexts to belong to the same block, since both the block and any
    * ICUs inside the block will each get their own context.
+   *
+   * This might be `null`, in which case the context is not associated with an i18n block. This
+   * probably means that it belongs to an i18n attribute.
    */
-  i18nBlock: XrefId;
+  i18nBlock: XrefId|null;
 
   /**
    * The i18n message associated with this context.
@@ -1129,8 +1150,12 @@ export interface I18nContextOp extends Op<CreateOp> {
 }
 
 export function createI18nContextOp(
-    contextKind: I18nContextKind, xref: XrefId, i18nBlock: XrefId, message: i18n.Message,
+    contextKind: I18nContextKind, xref: XrefId, i18nBlock: XrefId|null, message: i18n.Message,
     sourceSpan: ParseSourceSpan): I18nContextOp {
+  if (i18nBlock === null && contextKind !== I18nContextKind.Attr) {
+    throw new Error('AssertionError: i18nBlock must be provided for non-attribute contexts.');
+  }
+
   return {
     kind: OpKind.I18nContext,
     contextKind,
@@ -1144,6 +1169,33 @@ export function createI18nContextOp(
   };
 }
 
+export interface I18nAttributesOp extends Op<CreateOp>, ConsumesSlotOpTrait {
+  kind: OpKind.I18nAttributes;
+
+  /**
+   * The element targeted by these attributes.
+   */
+  target: XrefId;
+
+  /**
+   * I18nAttributes instructions correspond to a const array with configuration information.
+   */
+  i18nAttributesConfig: ConstIndex|null;
+}
+
+export function createI18nAttributesOp(
+    xref: XrefId, handle: SlotHandle, target: XrefId): I18nAttributesOp {
+  return {
+    kind: OpKind.I18nAttributes,
+    xref,
+    handle,
+    target,
+    i18nAttributesConfig: null,
+    ...NEW_OP,
+    ...TRAIT_CONSUMES_SLOT,
+  };
+}
+
 /**
  * An index into the `consts` array which is shared across the compilation of all views in a
  * component.

packages/compiler/src/template/pipeline/ir/src/ops/host.ts

@@ -9,7 +9,7 @@
 import * as o from '../../../../../../src/output/output_ast';
 import {ParseSourceSpan} from '../../../../../../src/parse_util';
 import {OpKind} from '../enums';
-import {Op} from '../operations';
+import {Op, XrefId} from '../operations';
 import {ConsumesVarsTrait, TRAIT_CONSUMES_VARS} from '../traits';
 
 import {NEW_OP} from './shared';
@@ -26,17 +26,21 @@ export interface HostPropertyOp extends Op<UpdateOp>, ConsumesVarsTrait {
   expression: o.Expression|Interpolation;
   isAnimationTrigger: boolean;
 
+  i18nContext: XrefId|null;
+
+
   sourceSpan: ParseSourceSpan|null;
 }
 
 export function createHostPropertyOp(
     name: string, expression: o.Expression|Interpolation, isAnimationTrigger: boolean,
-    sourceSpan: ParseSourceSpan|null): HostPropertyOp {
+    i18nContext: XrefId|null, sourceSpan: ParseSourceSpan|null): HostPropertyOp {
   return {
     kind: OpKind.HostProperty,
     name,
     expression,
     isAnimationTrigger,
+    i18nContext,
     sourceSpan,
     ...TRAIT_CONSUMES_VARS,
     ...NEW_OP,