Centralize duplicate-key detection behind scan_for_duplicate_keys

`ios_lint_localizations` open-coded a `strings_file_type == :text ? scan : warn` gate.
That logic now lives in `StringsFileValidationHelper.scan_for_duplicate_keys`, which
detects the file format and returns a `[:scanned | :unsupported_format | :unscannable,
payload]` tri-state; each caller maps it to its own policy. As a side effect,
`ios_lint_localizations`' `check_duplicate_keys` no longer crashes the lane on a
valid-but-not-flat-`.strings` file — it warns via `UI.important` and skips it.

Author: jkmassel

CHANGELOG.md

@@ -15,9 +15,11 @@ _None_
 ### Bug Fixes
 
 - `StringsFileValidationHelper.find_duplicated_keys` now parses *unquoted* keys and values (valid `.strings` syntax, common in `InfoPlist.strings`) instead of raising `Invalid character`, matching the character set `plutil` accepts for unquoted strings (alphanumerics plus `_ . - $ : /`). This lets `ios_lint_localizations`' `check_duplicate_keys` work on `InfoPlist.strings`-style files. [#____]
+- `ios_lint_localizations`' `check_duplicate_keys` no longer crashes the lane on a file that parses as a property list but isn't a flat `.strings` (e.g. a nested-dictionary value); it now warns via `UI.important` and skips that file. [#____]
 
 ### Internal Changes
 
+- Centralized `.strings` duplicate-key detection behind `StringsFileValidationHelper.scan_for_duplicate_keys`, which detects the file format and returns a `[:scanned | :unsupported_format | :unscannable, payload]` tri-state that callers map to their own policy (warn-and-skip vs fail-closed). `ios_lint_localizations` now uses it. [#____]
 - `L10nHelper.strings_file_type` (and `StringsFileValidationHelper.scan_for_duplicate_keys`) accept `assume_valid:` to skip a redundant `plutil -lint` when the caller has already parsed the file. [#____]
 
 ## 14.7.0

lib/fastlane/plugin/wpmreleasetoolkit/actions/ios/ios_lint_localizations.rb

@@ -56,15 +56,20 @@ def self.find_duplicated_keys(params)
           language = File.basename(File.dirname(file), '.lproj')
           path = File.join(params[:input_dir], file)
 
-          file_type = Fastlane::Helper::Ios::L10nHelper.strings_file_type(path: path)
-          if file_type == :text
-            duplicates = Fastlane::Helper::Ios::StringsFileValidationHelper.find_duplicated_keys(file: path)
-            duplicate_keys[language] = duplicates.map { |key, value| "`#{key}` was found at multiple lines: #{value.join(', ')}" } unless duplicates.empty?
-          else
+          status, payload = Fastlane::Helper::Ios::StringsFileValidationHelper.scan_for_duplicate_keys(file: path)
+          case status
+          when :scanned
+            duplicate_keys[language] = payload.map { |key, value| "`#{key}` was found at multiple lines: #{value.join(', ')}" } unless payload.empty?
+          when :unsupported_format
             UI.important <<~WRONG_FORMAT
-              File `#{path}` is in #{file_type} format, while finding duplicate keys only make sense on files that are in ASCII-plist format.
-              Since your files are in #{file_type} format, you should probably disable the `check_duplicate_keys` option from this `#{action_name}` call.
+              File `#{path}` is in #{payload} format, while finding duplicate keys only make sense on files that are in ASCII-plist format.
+              Since your files are in #{payload} format, you should probably disable the `check_duplicate_keys` option from this `#{action_name}` call.
             WRONG_FORMAT
+          when :unscannable
+            UI.important <<~UNSCANNABLE
+              Could not check `#{path}` for duplicate keys: #{payload.strip}
+              The file parses as a property list but isn't a flat `.strings` file the duplicate-key scanner understands, so duplicate detection was skipped for it.
+            UNSCANNABLE
           end
         end
 

lib/fastlane/plugin/wpmreleasetoolkit/helper/ios/ios_strings_file_validation_helper.rb

@@ -141,6 +141,28 @@ def self.find_duplicated_keys(file:)
 
           keys_with_lines.keep_if { |_, lines| lines.count > 1 }
         end
+
+        # Detects the file format and, when applicable, scans for duplicate keys — in one step, so
+        # callers don't each re-implement the "`:text`-only" gate. `find_duplicated_keys` only
+        # understands the flat ASCII-plist syntax; an xml/binary plist can't be tokenized by it (though
+        # `plutil` collapses any duplicate to its last value when parsing those anyway).
+        #
+        # @param [String] file The path to the `.strings` file to inspect.
+        # @param [Boolean] assume_valid Forwarded to `strings_file_type`: skip the redundant `plutil -lint`
+        #        when the caller has already confirmed the file parses.
+        # @return [Array] A `[status, payload]` pair, one of:
+        #         - `[:scanned, { key => [lines] }]` — a `:text` file we tokenized (hash empty if none).
+        #         - `[:unsupported_format, format]` — not a `:text` file (`:xml`, `:binary`, or `nil`); not scanned.
+        #         - `[:unscannable, error_message]` — a `:text` file the tokenizer couldn't read.
+        #         Each caller decides how to react (warn-and-skip, fail closed, …) from this one source of truth.
+        def self.scan_for_duplicate_keys(file:, assume_valid: false)
+          format = Fastlane::Helper::Ios::L10nHelper.strings_file_type(path: file, assume_valid: assume_valid)
+          return [:unsupported_format, format] unless format == :text
+
+          [:scanned, find_duplicated_keys(file: file)]
+        rescue StandardError => e
+          [:unscannable, e.message]
+        end
       end
     end
   end

spec/ios_lint_localizations_spec.rb

@@ -228,4 +228,54 @@ def run_l10n_linter_test(data_file:, check_duplicate_keys: nil, fail_on_strings_
       )
     end
   end
+
+  # Regression coverage for the unquoted-key/value parsing in `StringsFileValidationHelper`, which used
+  # to raise `Invalid character` on *unquoted* keys (valid `.strings` syntax, common in `InfoPlist.strings`)
+  # and so crashed `check_duplicate_keys`. It now parses unquoted keys and detects duplicates among them.
+  context 'duplicate-key detection on files with unquoted keys' do
+    let(:input_dir) { Dir.mktmpdir('a8c-lint-l10n-unquoted-') }
+
+    after { FileUtils.remove_entry(input_dir) }
+
+    def write_localizable(lang, content)
+      lproj = File.join(input_dir, "#{lang}.lproj")
+      FileUtils.mkdir_p(lproj)
+      File.write(File.join(lproj, 'Localizable.strings'), content)
+    end
+
+    it 'parses unquoted keys instead of raising, and detects duplicates among them' do
+      write_localizable('en', <<~STRINGS)
+        okay_key = "value";
+        NSCameraUsageDescription = "Take photos";
+        NSCameraUsageDescription = "Take a photo";
+        "quoted_key" = "value";
+      STRINGS
+
+      result = nil
+      expect { result = described_class.find_duplicated_keys({ input_dir: input_dir }) }.not_to raise_error
+      expect(result).to eq('en' => ['`NSCameraUsageDescription` was found at multiple lines: 2, 3'])
+    end
+
+    it 'reports no duplicates when unquoted keys are unique (mixed with quoted keys)' do
+      write_localizable('en', <<~STRINGS)
+        CFBundleName = "WordPress";
+        NSCameraUsageDescription = "Take photos";
+        "quoted_key" = "value";
+      STRINGS
+
+      expect(described_class.find_duplicated_keys({ input_dir: input_dir })).to eq({})
+    end
+
+    it 'warns and skips (without crashing) a file that parses as a plist but is not a flat `.strings`' do
+      # A nested-dictionary value is a valid old-style plist that `plutil` accepts but the duplicate-key
+      # scanner can't tokenize. This used to crash the lane (the scanner raised, uncaught); now it is
+      # surfaced via `UI.important` and the file is skipped.
+      write_localizable('en', "\"k\" = { a = b; };\n")
+      expect(FastlaneCore::UI).to receive(:important).with(/Could not check .* for duplicate keys/)
+
+      result = nil
+      expect { result = described_class.find_duplicated_keys({ input_dir: input_dir }) }.not_to raise_error
+      expect(result).to eq({})
+    end
+  end
 end

spec/ios_strings_file_validation_helper_spec.rb

@@ -97,4 +97,33 @@
       end
     end
   end
+
+  describe '.scan_for_duplicate_keys' do
+    it 'returns `[:scanned, duplicates]` for a `:text` file, with the duplicate hash (empty if none)' do
+      with_tmp_file(named: 'dups.strings', content: "\"k\" = \"a\";\n\"k\" = \"b\";\n") do |path|
+        expect(described_class.scan_for_duplicate_keys(file: path)).to eq([:scanned, { 'k' => [1, 2] }])
+      end
+      with_tmp_file(named: 'unique.strings', content: "\"k\" = \"a\";\n\"j\" = \"b\";\n") do |path|
+        expect(described_class.scan_for_duplicate_keys(file: path)).to eq([:scanned, {}])
+      end
+    end
+
+    it 'returns `[:unsupported_format, format]` for a non-`:text` (XML) plist, without scanning' do
+      in_tmp_dir do |dir|
+        path = File.join(dir, 'x.strings')
+        Fastlane::Helper::Ios::L10nHelper.generate_strings_file_from_hash(translations: { 'a' => 'b' }, output_path: path)
+        status, format = described_class.scan_for_duplicate_keys(file: path)
+        expect(status).to eq(:unsupported_format)
+        expect(format).to eq(:xml)
+      end
+    end
+
+    it 'returns `[:unscannable, message]` for a `:text` plist the tokenizer cannot read' do
+      with_tmp_file(named: 'nested.strings', content: "\"k\" = { a = b; };\n") do |path|
+        status, message = described_class.scan_for_duplicate_keys(file: path)
+        expect(status).to eq(:unscannable)
+        expect(message).to match(/Invalid character/)
+      end
+    end
+  end
 end