fix: honor pageRanges on macOS

docs/api/web-contents.md

@@ -1296,9 +1296,9 @@ Returns [`PrinterInfo[]`](structures/printer-info.md)
   * `pagesPerSheet` Number (optional) - The number of pages to print per page sheet.
   * `collate` Boolean (optional) - Whether the web page should be collated.
   * `copies` Number (optional) - The number of copies of the web page to print.
-  * `pageRanges` Record<string, number> (optional) - The page range to print.
-    * `from` Number - the start page.
-    * `to` Number - the end page.
+  * `pageRanges` Object[]  (optional) - The page range to print. On macOS, only one range is honored.
+    * `from` Number - Index of the first page to print (0-based).
+    * `to` Number - Index of the last page to print (inclusive) (0-based).
   * `duplexMode` String (optional) - Set the duplex mode of the printed web page. Can be `simplex`, `shortEdge`, or `longEdge`.
   * `dpi` Record<string, number> (optional)
     * `horizontal` Number (optional) - The horizontal dpi.
@@ -1324,10 +1324,10 @@ Example usage:
 const options = {
   silent: true,
   deviceName: 'My-Printer',
-  pageRanges: {
+  pageRanges: [{
     from: 0,
     to: 1
-  }
+  }]
 }
 win.webContents.print(options, (success, errorType) => {
   if (!success) console.log(errorType)
@@ -1345,8 +1345,8 @@ win.webContents.print(options, (success, errorType) => {
     default margin, 1 for no margin, and 2 for minimum margin.
   * `scaleFactor` Number (optional) - The scale factor of the web page. Can range from 0 to 100.
   * `pageRanges` Record<string, number> (optional) - The page range to print.
-    * `from` Number - zero-based index of the first page to print.
-    * `to` Number - zero-based index of the last page to print (inclusive).
+    * `from` Number - Index of the first page to print (0-based).
+    * `to` Number - Index of the last page to print (inclusive) (0-based).
   * `pageSize` String | Size (optional) - Specify page size of the generated PDF. Can be `A3`,
   `A4`, `A5`, `Legal`, `Letter`, `Tabloid` or an Object containing `height` and `width` in microns.
   * `printBackground` Boolean (optional) - Whether to print CSS backgrounds.

docs/api/webview-tag.md

@@ -560,9 +560,9 @@ Stops any `findInPage` request for the `webview` with the provided `action`.
   * `pagesPerSheet` Number (optional) - The number of pages to print per page sheet.
   * `collate` Boolean (optional) - Whether the web page should be collated.
   * `copies` Number (optional) - The number of copies of the web page to print.
-  * `pageRanges` Record<string, number> (optional) - The page range to print.
-    * `from` Number - zero-based index of the first page to print.
-    * `to` Number - zero-based index of the last page to print (inclusive).
+  * `pageRanges` Object[]  (optional) - The page range to print.
+    * `from` Number - Index of the first page to print (1-based).
+    * `to` Number - Index of the last page to print (inclusive) (1-based).
   * `duplexMode` String (optional) - Set the duplex mode of the printed web page. Can be `simplex`, `shortEdge`, or `longEdge`.
   * `dpi` Record<string, number> (optional)
     * `horizontal` Number (optional) - The horizontal dpi.
@@ -587,9 +587,9 @@ Prints `webview`'s web page. Same as `webContents.print([options])`.
     default margin, 1 for no margin, and 2 for minimum margin.
     and `width` in microns.
   * `scaleFactor` Number (optional) - The scale factor of the web page. Can range from 0 to 100.
-  * `pageRanges` Record<string, number> (optional) - The page range to print.
-    * `from` Number - the first page to print.
-    * `to` Number - the last page to print (inclusive).
+  * `pageRanges` Record<string, number> (optional) - The page range to print. On macOS, only the first range is honored.
+    * `from` Number - Index of the first page to print (0-based).
+    * `to` Number - Index of the last page to print (inclusive) (0-based).
   * `pageSize` String | Size (optional) - Specify page size of the generated PDF. Can be `A3`,
   `A4`, `A5`, `Legal`, `Letter`, `Tabloid` or an Object containing `height`
   * `printBackground` Boolean (optional) - Whether to print CSS backgrounds.

patches/chromium/.patches

@@ -100,3 +100,4 @@ remove_some_deps_that_do_not_work_on_arm64.patch
 fix_check_issecureeventinputenabled_in_constructor_before_setting.patch
 skip_atk_toolchain_check.patch
 worker_feat_add_hook_to_notify_script_ready.patch
+fix_properly_honor_print_range_on_macos.patch

patches/chromium/fix_properly_honor_print_range_on_macos.patch

@@ -0,0 +1,63 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Shelley Vohr <shelley.vohr@gmail.com>
+Date: Thu, 20 Aug 2020 10:55:48 -0700
+Subject: fix: properly honor print range on macOS
+
+The print ranges in Chromium's print job settings were not being properly
+plumbed through to PMPrintSettings on mcOS. This fixes that by setting
+them should they exist.
+
+This will be upstreamed.
+
+diff --git a/printing/printing_context_mac.h b/printing/printing_context_mac.h
+index 06cdc0e1a4a50e29a148c97c964c30a939e800da..5db5cdb61be0beee4506313dcde46c499e011383 100644
+--- a/printing/printing_context_mac.h
++++ b/printing/printing_context_mac.h
+@@ -81,6 +81,10 @@ class PRINTING_EXPORT PrintingContextMac : public PrintingContext {
+   // Returns true if the orientation was set.
+   bool SetOrientationIsLandscape(bool landscape);
+
++  // Set the page range in native print info object.
++  // Returns true if the range was set.
++  bool SetPrintRangeInPrintSettings(const PageRanges& ranges);
++
+   // Sets duplex mode in PMPrintSettings.
+   // Returns true if duplex mode is set.
+   bool SetDuplexModeInPrintSettings(mojom::DuplexMode mode);
+diff --git a/printing/printing_context_mac.mm b/printing/printing_context_mac.mm
+index 56bcfbe625537c7b1bc2a999c261836bb15896ba..3965b877718160ce55e7c97d75e8992f45ac3f2f 100644
+--- a/printing/printing_context_mac.mm
++++ b/printing/printing_context_mac.mm
+@@ -188,7 +188,8 @@ PMPaper MatchPaper(CFArrayRef paper_list,
+         !SetCopiesInPrintSettings(settings_->copies()) ||
+         !SetCollateInPrintSettings(settings_->collate()) ||
+         !SetDuplexModeInPrintSettings(settings_->duplex_mode()) ||
+-        !SetOutputColor(settings_->color())) {
++        !SetOutputColor(settings_->color()) ||
++        !SetPrintRangeInPrintSettings(settings_->ranges()) ) {
+       return OnError();
+     }
+   }
+@@ -341,6 +342,22 @@ PMPaper MatchPaper(CFArrayRef paper_list,
+   return PMSetCopies(print_settings, copies, false) == noErr;
+ }
+
++bool PrintingContextMac::SetPrintRangeInPrintSettings(const PageRanges& ranges) {
++  // Default is already NSPrintAllPages - we can safely bail.
++  if (ranges.empty())
++    return true; 
++
++  PMPrintSettings print_settings =
++      static_cast<PMPrintSettings>([print_info_.get() PMPrintSettings]);
++
++  // macOS does not allow multiple ranges, so pluck the first.
++  auto range = ranges.front();
++  bool set_first_page = PMSetFirstPage(print_settings, range.from + 1, false) == noErr;
++  bool set_last_page = PMSetLastPage(print_settings, range.to + 1, false) == noErr;
++
++  return set_first_page && set_last_page;
++}
++
+ bool PrintingContextMac::SetCollateInPrintSettings(bool collate) {
+   PMPrintSettings print_settings =
+       static_cast<PMPrintSettings>([print_info_.get() PMPrintSettings]);

shell/browser/api/electron_api_web_contents.cc

@@ -2073,8 +2073,9 @@ void WebContents::Print(gin::Arguments* args) {
       int from, to;
       if (range.Get("from", &from) && range.Get("to", &to)) {
         base::Value range(base::Value::Type::DICTIONARY);
-        range.SetIntKey(printing::kSettingPageRangeFrom, from);
-        range.SetIntKey(printing::kSettingPageRangeTo, to);
+        // Chromium uses 1-based page ranges, so increment each by 1.
+        range.SetIntKey(printing::kSettingPageRangeFrom, from + 1);
+        range.SetIntKey(printing::kSettingPageRangeTo, to + 1);
         page_range_list.Append(std::move(range));
       } else {
         continue;