Merge pull request #13050 from Snuffleupagus/l10n-fallback

Collect all l10n fallback strings, used in the viewer, in one helper function (PR 12981 follow-up)

web/annotation_layer_builder.js

@@ -14,7 +14,7 @@
  */
 
 import { AnnotationLayer } from "pdfjs-lib";
-import { NullL10n } from "./ui_utils.js";
+import { NullL10n } from "./l10n_utils.js";
 import { SimpleLinkService } from "./pdf_link_service.js";
 
 /**

web/app.js

@@ -260,28 +260,6 @@ const PDFViewerApplication = {
   _scriptingInstance: null,
   _mouseState: Object.create(null),
 
-  _localizeMessage(key, args = null) {
-    const DEFAULT_L10N_STRINGS = {
-      error_file: "File: {{file}}",
-      error_line: "Line: {{line}}",
-      error_message: "Message: {{message}}",
-      error_stack: "Stack: {{stack}}",
-      error_version_info: "PDF.js v{{version}} (build: {{build}})",
-      invalid_file_error: "Invalid or corrupted PDF file.",
-      loading_error: "An error occurred while loading the PDF.",
-      missing_file_error: "Missing PDF file.",
-      printing_not_ready: "Warning: The PDF is not fully loaded for printing.",
-      printing_not_supported:
-        "Warning: Printing is not fully supported by this browser.",
-      rendering_error: "An error occurred while rendering the page.",
-      unexpected_response_error: "Unexpected server response.",
-      web_fonts_disabled:
-        "Web fonts are disabled: unable to use embedded PDF fonts.",
-    };
-
-    return this.l10n.get(key || "", args, DEFAULT_L10N_STRINGS[key]);
-  },
-
   // Called once when the document is loaded.
   async initialize(appConfig) {
     this.preferences = this.externalServices.createPreferences();
@@ -741,7 +719,7 @@ const PDFViewerApplication = {
         this.open(file, args);
       },
       onError: err => {
-        this._localizeMessage("loading_error").then(msg => {
+        this.l10n.get("loading_error").then(msg => {
           this._documentError(msg, err);
         });
       },
@@ -973,7 +951,7 @@ const PDFViewerApplication = {
         } else if (exception instanceof UnexpectedResponseException) {
           key = "unexpected_response_error";
         }
-        return this._localizeMessage(key).then(msg => {
+        return this.l10n.get(key).then(msg => {
           this._documentError(msg, { message: exception?.message });
           throw exception;
         });
@@ -1128,28 +1106,28 @@ const PDFViewerApplication = {
    */
   _otherError(message, moreInfo = null) {
     const moreInfoText = [
-      this._localizeMessage("error_version_info", {
+      this.l10n.get("error_version_info", {
         version: version || "?",
         build: build || "?",
       }),
     ];
     if (moreInfo) {
       moreInfoText.push(
-        this._localizeMessage("error_message", { message: moreInfo.message })
+        this.l10n.get("error_message", { message: moreInfo.message })
       );
       if (moreInfo.stack) {
         moreInfoText.push(
-          this._localizeMessage("error_stack", { stack: moreInfo.stack })
+          this.l10n.get("error_stack", { stack: moreInfo.stack })
         );
       } else {
         if (moreInfo.filename) {
           moreInfoText.push(
-            this._localizeMessage("error_file", { file: moreInfo.filename })
+            this.l10n.get("error_file", { file: moreInfo.filename })
           );
         }
         if (moreInfo.lineNumber) {
           moreInfoText.push(
-            this._localizeMessage("error_line", { line: moreInfo.lineNumber })
+            this.l10n.get("error_line", { line: moreInfo.lineNumber })
           );
         }
       }
@@ -2021,7 +1999,7 @@ const PDFViewerApplication = {
     }
 
     if (!this.supportsPrinting) {
-      this._localizeMessage("printing_not_supported").then(msg => {
+      this.l10n.get("printing_not_supported").then(msg => {
         this._otherError(msg);
       });
       return;
@@ -2030,7 +2008,7 @@ const PDFViewerApplication = {
     // The beforePrint is a sync method and we need to know layout before
     // returning from this method. Ensure that we can get sizes of the pages.
     if (!this.pdfViewer.pageViewsReady) {
-      this._localizeMessage("printing_not_ready").then(msg => {
+      this.l10n.get("printing_not_ready").then(msg => {
         // eslint-disable-next-line no-alert
         window.alert(msg);
       });
@@ -2354,7 +2332,7 @@ if (typeof PDFJSDev === "undefined" || PDFJSDev.test("GENERIC")) {
         throw new Error("file origin does not match viewer's");
       }
     } catch (ex) {
-      PDFViewerApplication._localizeMessage("loading_error").then(msg => {
+      PDFViewerApplication.l10n.get("loading_error").then(msg => {
         PDFViewerApplication._documentError(msg, { message: ex?.message });
       });
       throw ex;
@@ -2465,7 +2443,7 @@ function webViewerInitialized() {
 
   if (!PDFViewerApplication.supportsDocumentFonts) {
     AppOptions.set("disableFontFace", true);
-    PDFViewerApplication._localizeMessage("web_fonts_disabled").then(msg => {
+    PDFViewerApplication.l10n.get("web_fonts_disabled").then(msg => {
       console.warn(msg);
     });
   }
@@ -2497,7 +2475,7 @@ function webViewerInitialized() {
   try {
     webViewerOpenFileViaURL(file);
   } catch (reason) {
-    PDFViewerApplication._localizeMessage("loading_error").then(msg => {
+    PDFViewerApplication.l10n.get("loading_error").then(msg => {
       PDFViewerApplication._documentError(msg, reason);
     });
   }
@@ -2568,7 +2546,7 @@ function webViewerPageRendered({ pageNumber, timestamp, error }) {
   }
 
   if (error) {
-    PDFViewerApplication._localizeMessage("rendering_error").then(msg => {
+    PDFViewerApplication.l10n.get("rendering_error").then(msg => {
       PDFViewerApplication._otherError(msg, error);
     });
   }

web/base_viewer.js

@@ -25,7 +25,6 @@ import {
   isValidSpreadMode,
   MAX_AUTO_SCALE,
   moveToEndOfArray,
-  NullL10n,
   PresentationModeState,
   RendererType,
   SCROLLBAR_PADDING,
@@ -39,6 +38,7 @@ import {
 } from "./ui_utils.js";
 import { PDFRenderingQueue, RenderingStates } from "./pdf_rendering_queue.js";
 import { AnnotationLayerBuilder } from "./annotation_layer_builder.js";
+import { NullL10n } from "./l10n_utils.js";
 import { PDFPageView } from "./pdf_page_view.js";
 import { SimpleLinkService } from "./pdf_link_service.js";
 import { TextLayerBuilder } from "./text_layer_builder.js";

web/firefoxcom.js

@@ -18,6 +18,7 @@ import { DefaultExternalServices, PDFViewerApplication } from "./app.js";
 import { isPdfFile, PDFDataRangeTransport, shadow } from "pdfjs-lib";
 import { BasePreferences } from "./preferences.js";
 import { DEFAULT_SCALE_VALUE } from "./ui_utils.js";
+import { getL10nFallback } from "./l10n_utils.js";
 
 if (typeof PDFJSDev === "undefined" || !PDFJSDev.test("MOZCENTRAL")) {
   throw new Error(
@@ -200,8 +201,8 @@ class MozL10n {
     return this.mozL10n.getDirection();
   }
 
-  async get(property, args, fallback) {
+  async get(key, args = null, fallback = getL10nFallback(key, args)) {
-    return this.mozL10n.get(property, args, fallback);
+    return this.mozL10n.get(key, args, fallback);
   }
 
   async translate(element) {

web/genericl10n.js

@@ -14,6 +14,7 @@
  */
 
 import "../external/webL10n/l10n.js";
+import { getL10nFallback } from "./l10n_utils.js";
 
 const webL10n = document.webL10n;
 
@@ -37,9 +38,9 @@ class GenericL10n {
     return l10n.getDirection();
   }
 
-  async get(property, args, fallback) {
+  async get(key, args = null, fallback = getL10nFallback(key, args)) {
     const l10n = await this._ready;
-    return l10n.get(property, args, fallback);
+    return l10n.get(key, args, fallback);
   }
 
   async translate(element) {

web/l10n_utils.js

@@ -0,0 +1,127 @@
+/* Copyright 2021 Mozilla Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * A subset of the l10n strings in the `l10n/en-US/viewer.properties` file.
+ */
+const DEFAULT_L10N_STRINGS = {
+  of_pages: "of {{pagesCount}}",
+  page_of_pages: "({{pageNumber}} of {{pagesCount}})",
+
+  document_properties_kb: "{{size_kb}} KB ({{size_b}} bytes)",
+  document_properties_mb: "{{size_mb}} MB ({{size_b}} bytes)",
+  document_properties_date_string: "{{date}}, {{time}}",
+  document_properties_page_size_unit_inches: "in",
+  document_properties_page_size_unit_millimeters: "mm",
+  document_properties_page_size_orientation_portrait: "portrait",
+  document_properties_page_size_orientation_landscape: "landscape",
+  document_properties_page_size_name_a3: "A3",
+  document_properties_page_size_name_a4: "A4",
+  document_properties_page_size_name_letter: "Letter",
+  document_properties_page_size_name_legal: "Legal",
+  document_properties_page_size_dimension_string:
+    "{{width}} × {{height}} {{unit}} ({{orientation}})",
+  document_properties_page_size_dimension_name_string:
+    "{{width}} × {{height}} {{unit}} ({{name}}, {{orientation}})",
+  document_properties_linearized_yes: "Yes",
+  document_properties_linearized_no: "No",
+
+  print_progress_percent: "{{progress}}%",
+
+  "toggle_sidebar.title": "Toggle Sidebar",
+  "toggle_sidebar_notification2.title":
+    "Toggle Sidebar (document contains outline/attachments/layers)",
+
+  additional_layers: "Additional Layers",
+  page_canvas: "Page {{page}}",
+  thumb_page_title: "Page {{page}}",
+  thumb_page_canvas: "Thumbnail of Page {{page}}",
+
+  find_reached_top: "Reached top of document, continued from bottom",
+  find_reached_bottom: "Reached end of document, continued from top",
+  "find_match_count[one]": "{{current}} of {{total}} match",
+  "find_match_count[other]": "{{current}} of {{total}} matches",
+  "find_match_count_limit[one]": "More than {{limit}} match",
+  "find_match_count_limit[other]": "More than {{limit}} matches",
+  find_not_found: "Phrase not found",
+
+  error_version_info: "PDF.js v{{version}} (build: {{build}})",
+  error_message: "Message: {{message}}",
+  error_stack: "Stack: {{stack}}",
+  error_file: "File: {{file}}",
+  error_line: "Line: {{line}}",
+  rendering_error: "An error occurred while rendering the page.",
+
+  page_scale_width: "Page Width",
+  page_scale_fit: "Page Fit",
+  page_scale_auto: "Automatic Zoom",
+  page_scale_actual: "Actual Size",
+  page_scale_percent: "{{scale}}%",
+
+  loading_error: "An error occurred while loading the PDF.",
+  invalid_file_error: "Invalid or corrupted PDF file.",
+  missing_file_error: "Missing PDF file.",
+  unexpected_response_error: "Unexpected server response.",
+
+  printing_not_supported:
+    "Warning: Printing is not fully supported by this browser.",
+  printing_not_ready: "Warning: The PDF is not fully loaded for printing.",
+  web_fonts_disabled:
+    "Web fonts are disabled: unable to use embedded PDF fonts.",
+};
+
+function getL10nFallback(key, args) {
+  switch (key) {
+    case "find_match_count":
+      key = `find_match_count[${args.total === 1 ? "one" : "other"}]`;
+      break;
+    case "find_match_count_limit":
+      key = `find_match_count_limit[${args.limit === 1 ? "one" : "other"}]`;
+      break;
+  }
+  return DEFAULT_L10N_STRINGS[key] || "";
+}
+
+// Replaces {{arguments}} with their values.
+function formatL10nValue(text, args) {
+  if (!args) {
+    return text;
+  }
+  return text.replace(/\{\{\s*(\w+)\s*\}\}/g, (all, name) => {
+    return name in args ? args[name] : "{{" + name + "}}";
+  });
+}
+
+/**
+ * No-op implementation of the localization service.
+ * @implements {IL10n}
+ */
+const NullL10n = {
+  async getLanguage() {
+    return "en-us";
+  },
+
+  async getDirection() {
+    return "ltr";
+  },
+
+  async get(key, args = null, fallback = getL10nFallback(key, args)) {
+    return formatL10nValue(fallback, args);
+  },
+
+  async translate(element) {},
+};
+
+export { getL10nFallback, NullL10n };

web/password_prompt.js

@@ -67,34 +67,18 @@ class PasswordPrompt {
     );
   }
 
-  open() {
+  async open() {
-    this.overlayManager.open(this.overlayName).then(() => {
+    await this.overlayManager.open(this.overlayName);
-      if (
-        !this._isViewerEmbedded ||
-        this.reason === PasswordResponses.INCORRECT_PASSWORD
-      ) {
-        this.input.focus();
-      }
 
-      let promptString;
+    const passwordIncorrect =
-      if (this.reason === PasswordResponses.INCORRECT_PASSWORD) {
+      this.reason === PasswordResponses.INCORRECT_PASSWORD;
-        promptString = this.l10n.get(
-          "password_invalid",
-          null,
-          "Invalid password. Please try again."
-        );
-      } else {
-        promptString = this.l10n.get(
-          "password_label",
-          null,
-          "Enter the password to open this PDF file."
-        );
-      }
 
-      promptString.then(msg => {
+    if (!this._isViewerEmbedded || passwordIncorrect) {
-        this.label.textContent = msg;
+      this.input.focus();
-      });
+    }
-    });
+    this.label.textContent = await this.l10n.get(
+      `password_${passwordIncorrect ? "invalid" : "label"}`
+    );
   }
 
   close() {

web/pdf_document_properties.js

@@ -255,27 +255,16 @@ class PDFDocumentProperties {
    * @private
    */
   async _parseFileSize(fileSize = 0) {
-    const kb = fileSize / 1024;
+    const kb = fileSize / 1024,
+      mb = kb / 1024;
     if (!kb) {
       return undefined;
-    } else if (kb < 1024) {
-      return this.l10n.get(
-        "document_properties_kb",
-        {
-          size_kb: (+kb.toPrecision(3)).toLocaleString(),
-          size_b: fileSize.toLocaleString(),
-        },
-        "{{size_kb}} KB ({{size_b}} bytes)"
-      );
     }
-    return this.l10n.get(
+    return this.l10n.get(`document_properties_${mb >= 1 ? "mb" : "kb"}`, {
-      "document_properties_mb",
+      size_mb: mb >= 1 && (+mb.toPrecision(3)).toLocaleString(),
-      {
+      size_kb: (+kb.toPrecision(3)).toLocaleString(),
-        size_mb: (+(kb / 1024).toPrecision(3)).toLocaleString(),
+      size_b: fileSize.toLocaleString(),
-        size_b: fileSize.toLocaleString(),
+    });
-      },
-      "{{size_mb}} MB ({{size_b}} bytes)"
-    );
   }
 
   /**
@@ -304,7 +293,6 @@ class PDFDocumentProperties {
       height: Math.round(pageSizeInches.height * 25.4 * 10) / 10,
     };
 
-    let pageName = null;
     let rawName =
       getPageName(sizeInches, isPortrait, US_PAGE_NAMES) ||
       getPageName(sizeMillimeters, isPortrait, METRIC_PAGE_NAMES);
@@ -345,46 +333,35 @@ class PDFDocumentProperties {
         }
       }
     }
-    if (rawName) {
-      pageName = this.l10n.get(
-        "document_properties_page_size_name_" + rawName.toLowerCase(),
-        null,
-        rawName
-      );
-    }
 
-    return Promise.all([
+    const [{ width, height }, unit, name, orientation] = await Promise.all([
       this._isNonMetricLocale ? sizeInches : sizeMillimeters,
       this.l10n.get(
-        "document_properties_page_size_unit_" +
+        `document_properties_page_size_unit_${
-          (this._isNonMetricLocale ? "inches" : "millimeters"),
+          this._isNonMetricLocale ? "inches" : "millimeters"
-        null,
+        }`
-        this._isNonMetricLocale ? "in" : "mm"
       ),
-      pageName,
+      rawName &&
+        this.l10n.get(
+          `document_properties_page_size_name_${rawName.toLowerCase()}`
+        ),
       this.l10n.get(
-        "document_properties_page_size_orientation_" +
+        `document_properties_page_size_orientation_${
-          (isPortrait ? "portrait" : "landscape"),
+          isPortrait ? "portrait" : "landscape"
-        null,
+        }`
-        isPortrait ? "portrait" : "landscape"
       ),
-    ]).then(([{ width, height }, unit, name, orientation]) => {
+    ]);
-      return this.l10n.get(
+
-        "document_properties_page_size_dimension_" +
+    return this.l10n.get(
-          (name ? "name_" : "") +
+      `document_properties_page_size_dimension_${name ? "name_" : ""}string`,
-          "string",
+      {
-        {
+        width: width.toLocaleString(),
-          width: width.toLocaleString(),
+        height: height.toLocaleString(),
-          height: height.toLocaleString(),
+        unit,
-          unit,
+        name,
-          name,
+        orientation,
-          orientation,
+      }
-        },
+    );
-        "{{width}} × {{height}} {{unit}} (" +
-          (name ? "{{name}}, " : "") +
-          "{{orientation}})"
-      );
-    });
   }
 
   /**
@@ -395,14 +372,10 @@ class PDFDocumentProperties {
     if (!dateObject) {
       return undefined;
     }
-    return this.l10n.get(
+    return this.l10n.get("document_properties_date_string", {
-      "document_properties_date_string",
+      date: dateObject.toLocaleDateString(),
-      {
+      time: dateObject.toLocaleTimeString(),
-        date: dateObject.toLocaleDateString(),
+    });
-        time: dateObject.toLocaleTimeString(),
-      },
-      "{{date}}, {{time}}"
-    );
   }
 
   /**
@@ -410,9 +383,7 @@ class PDFDocumentProperties {
    */
   _parseLinearization(isLinearized) {
     return this.l10n.get(
-      "document_properties_linearized_" + (isLinearized ? "yes" : "no"),
+      `document_properties_linearized_${isLinearized ? "yes" : "no"}`
-      null,
-      isLinearized ? "Yes" : "No"
     );
   }
 }

web/pdf_find_bar.js

@@ -103,41 +103,26 @@ class PDFFindBar {
   }
 
   updateUIState(state, previous, matchesCount) {
-    let findMsg = "";
+    let findMsg = Promise.resolve("");
     let status = "";
 
     switch (state) {
       case FindState.FOUND:
         break;
-
       case FindState.PENDING:
         status = "pending";
         break;
-
       case FindState.NOT_FOUND:
-        findMsg = this.l10n.get("find_not_found", null, "Phrase not found");
+        findMsg = this.l10n.get("find_not_found");
         status = "notFound";
         break;
-
       case FindState.WRAPPED:
-        if (previous) {
+        findMsg = this.l10n.get(`find_reached_${previous ? "top" : "bottom"}`);
-          findMsg = this.l10n.get(
-            "find_reached_top",
-            null,
-            "Reached top of document, continued from bottom"
-          );
-        } else {
-          findMsg = this.l10n.get(
-            "find_reached_bottom",
-            null,
-            "Reached end of document, continued from top"
-          );
-        }
         break;
     }
     this.findField.setAttribute("data-status", status);
 
-    Promise.resolve(findMsg).then(msg => {
+    findMsg.then(msg => {
       this.findMsg.textContent = msg;
       this._adjustWidth();
     });
@@ -147,54 +132,30 @@ class PDFFindBar {
 
   updateResultsCount({ current = 0, total = 0 } = {}) {
     const limit = MATCHES_COUNT_LIMIT;
-    let matchesCountMsg = "";
+    let matchCountMsg = Promise.resolve("");
 
     if (total > 0) {
       if (total > limit) {
+        let key = "find_match_count_limit";
+
         if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
           // TODO: Remove this hard-coded `[other]` form once plural support has
           // been implemented in the mozilla-central specific `l10n.js` file.
-          matchesCountMsg = this.l10n.get(
+          key += "[other]";
-            "find_match_count_limit[other]",
-            {
-              limit,
-            },
-            "More than {{limit}} matches"
-          );
-        } else {
-          matchesCountMsg = this.l10n.get(
-            "find_match_count_limit",
-            {
-              limit,
-            },
-            "More than {{limit}} match" + (limit !== 1 ? "es" : "")
-          );
         }
+        matchCountMsg = this.l10n.get(key, { limit });
       } else {
+        let key = "find_match_count";
+
         if (typeof PDFJSDev !== "undefined" && PDFJSDev.test("MOZCENTRAL")) {
           // TODO: Remove this hard-coded `[other]` form once plural support has
           // been implemented in the mozilla-central specific `l10n.js` file.
-          matchesCountMsg = this.l10n.get(
+          key += "[other]";
-            "find_match_count[other]",
-            {
-              current,
-              total,
-            },
-            "{{current}} of {{total}} matches"
-          );
-        } else {
-          matchesCountMsg = this.l10n.get(
-            "find_match_count",
-            {
-              current,
-              total,
-            },
-            "{{current}} of {{total}} match" + (total !== 1 ? "es" : "")
-          );
         }
+        matchCountMsg = this.l10n.get(key, { current, total });
       }
     }
-    Promise.resolve(matchesCountMsg).then(msg => {
+    matchCountMsg.then(msg => {
       this.findResultsCount.textContent = msg;
       this.findResultsCount.classList.toggle("hidden", !total);
       // Since `updateResultsCount` may be called from `PDFFindController`,

web/pdf_layer_viewer.js

@@ -87,11 +87,7 @@ class PDFLayerViewer extends BaseTreeViewer {
       element.textContent = this._normalizeTextContent(name);
       return;
     }
-    element.textContent = await this.l10n.get(
+    element.textContent = await this.l10n.get("additional_layers");
-      "additional_layers",
-      null,
-      "Additional Layers"
-    );
     element.style.fontStyle = "italic";
   }
 

web/pdf_page_view.js

@@ -18,7 +18,6 @@ import {
   CSS_UNITS,
   DEFAULT_SCALE,
   getOutputScale,
-  NullL10n,
   RendererType,
   roundToDivide,
   TextLayerMode,
@@ -28,6 +27,7 @@ import {
   RenderingCancelledException,
   SVGGraphics,
 } from "pdfjs-lib";
+import { NullL10n } from "./l10n_utils.js";
 import { RenderingStates } from "./pdf_rendering_queue.js";
 import { viewerCompatibilityParams } from "./viewer_compatibility.js";
 
@@ -576,11 +576,9 @@ class PDFPageView {
 
     const viewport = this.viewport;
     const canvas = document.createElement("canvas");
-    this.l10n
+    this.l10n.get("page_canvas", { page: this.id }).then(msg => {
-      .get("page_canvas", { page: this.id }, "Page {{page}}")
+      canvas.setAttribute("aria-label", msg);
-      .then(msg => {
+    });
-        canvas.setAttribute("aria-label", msg);
-      });
 
     // Keep the canvas hidden until the first draw callback, or until drawing
     // is complete when `!this.renderingQueue`, to prevent black flickering.

web/pdf_print_service.js

@@ -308,7 +308,7 @@ function renderProgress(index, total, l10n) {
   const progressBar = progressContainer.querySelector("progress");
   const progressPerc = progressContainer.querySelector(".relative-progress");
   progressBar.value = progress;
-  l10n.get("print_progress_percent", { progress }, progress + "%").then(msg => {
+  l10n.get("print_progress_percent", { progress }).then(msg => {
     progressPerc.textContent = msg;
   });
 }

web/pdf_sidebar.js

@@ -339,15 +339,9 @@ class PDFSidebar {
    * @private
    */
   _showUINotification() {
-    this.l10n
+    this.l10n.get("toggle_sidebar_notification2.title").then(msg => {
-      .get(
+      this.toggleButton.title = msg;
-        "toggle_sidebar_notification2.title",
+    });
-        null,
-        "Toggle Sidebar (document contains outline/attachments/layers)"
-      )
-      .then(msg => {
-        this.toggleButton.title = msg;
-      });
 
     if (!this.isOpen) {
       // Only show the notification on the `toggleButton` if the sidebar is
@@ -367,11 +361,9 @@ class PDFSidebar {
     }
 
     if (reset) {
-      this.l10n
+      this.l10n.get("toggle_sidebar.title").then(msg => {
-        .get("toggle_sidebar.title", null, "Toggle Sidebar")
+        this.toggleButton.title = msg;
-        .then(msg => {
+      });
-          this.toggleButton.title = msg;
-        });
     }
   }
 

web/pdf_thumbnail_view.js

@@ -467,19 +467,15 @@ class PDFThumbnailView {
   }
 
   get _thumbPageTitle() {
-    return this.l10n.get(
+    return this.l10n.get("thumb_page_title", {
-      "thumb_page_title",
+      page: this.pageLabel ?? this.id,
-      { page: this.pageLabel ?? this.id },
+    });
-      "Page {{page}}"
-    );
   }
 
   get _thumbPageCanvas() {
-    return this.l10n.get(
+    return this.l10n.get("thumb_page_canvas", {
-      "thumb_page_canvas",
+      page: this.pageLabel ?? this.id,
-      { page: this.pageLabel ?? this.id },
+    });
-      "Thumbnail of Page {{page}}"
-    );
   }
 
   /**

web/pdf_viewer.component.js

@@ -21,10 +21,11 @@ import {
   DefaultTextLayerFactory,
   TextLayerBuilder,
 } from "./text_layer_builder.js";
-import { EventBus, NullL10n, ProgressBar } from "./ui_utils.js";
+import { EventBus, ProgressBar } from "./ui_utils.js";
 import { PDFLinkService, SimpleLinkService } from "./pdf_link_service.js";
 import { DownloadManager } from "./download_manager.js";
 import { GenericL10n } from "./genericl10n.js";
+import { NullL10n } from "./l10n_utils.js";
 import { PDFFindController } from "./pdf_find_controller.js";
 import { PDFHistory } from "./pdf_history.js";
 import { PDFPageView } from "./pdf_page_view.js";

web/toolbar.js

@@ -177,26 +177,18 @@ class Toolbar {
         items.pageNumber.type = "text";
       } else {
         items.pageNumber.type = "number";
-        this.l10n
+        this.l10n.get("of_pages", { pagesCount }).then(msg => {
-          .get("of_pages", { pagesCount }, "of {{pagesCount}}")
+          items.numPages.textContent = msg;
-          .then(msg => {
+        });
-            items.numPages.textContent = msg;
-          });
       }
       items.pageNumber.max = pagesCount;
     }
 
     if (this.hasPageLabels) {
       items.pageNumber.value = this.pageLabel;
-      this.l10n
+      this.l10n.get("page_of_pages", { pageNumber, pagesCount }).then(msg => {
-        .get(
+        items.numPages.textContent = msg;
-          "page_of_pages",
+      });
-          { pageNumber, pagesCount },
-          "({{pageNumber}} of {{pagesCount}})"
-        )
-        .then(msg => {
-          items.numPages.textContent = msg;
-        });
     } else {
       items.pageNumber.value = pageNumber;
     }
@@ -207,9 +199,8 @@ class Toolbar {
     items.zoomOut.disabled = pageScale <= MIN_SCALE;
     items.zoomIn.disabled = pageScale >= MAX_SCALE;
 
-    const customScale = Math.round(pageScale * 10000) / 100;
     this.l10n
-      .get("page_scale_percent", { scale: customScale }, "{{scale}}%")
+      .get("page_scale_percent", { scale: Math.round(pageScale * 10000) / 100 })
       .then(msg => {
         let predefinedValueFound = false;
         for (const option of items.scaleSelect.options) {
@@ -242,10 +233,10 @@ class Toolbar {
     const { items, l10n } = this;
 
     const predefinedValuesPromise = Promise.all([
-      l10n.get("page_scale_auto", null, "Automatic Zoom"),
+      l10n.get("page_scale_auto"),
-      l10n.get("page_scale_actual", null, "Actual Size"),
+      l10n.get("page_scale_actual"),
-      l10n.get("page_scale_fit", null, "Page Fit"),
+      l10n.get("page_scale_fit"),
-      l10n.get("page_scale_width", null, "Page Width"),
+      l10n.get("page_scale_width"),
     ]);
 
     // The temporary canvas is used to measure text length in the DOM.

web/ui_utils.js

@@ -69,36 +69,6 @@ const SpreadMode = {
 // Used by `PDFViewerApplication`, and by the API unit-tests.
 const AutoPrintRegExp = /\bprint\s*\(/;
 
-// Replaces {{arguments}} with their values.
-function formatL10nValue(text, args) {
-  if (!args) {
-    return text;
-  }
-  return text.replace(/\{\{\s*(\w+)\s*\}\}/g, (all, name) => {
-    return name in args ? args[name] : "{{" + name + "}}";
-  });
-}
-
-/**
- * No-op implementation of the localization service.
- * @implements {IL10n}
- */
-const NullL10n = {
-  async getLanguage() {
-    return "en-us";
-  },
-
-  async getDirection() {
-    return "ltr";
-  },
-
-  async get(property, args, fallback) {
-    return formatL10nValue(fallback, args);
-  },
-
-  async translate(element) {},
-};
-
 /**
  * Returns scale factor for the canvas. It makes sense for the HiDPI displays.
  * @returns {Object} The object with horizontal (sx) and vertical (sy)
@@ -1057,7 +1027,6 @@ export {
   noContextMenuHandler,
   normalizeWheelEventDelta,
   normalizeWheelEventDirection,
-  NullL10n,
   parseQueryString,
   PresentationModeState,
   ProgressBar,