Add custom prefix configuration to DerivedBuildCodeFormatter

CHANGELOG.md

@@ -10,7 +10,7 @@ _None_
 
 ### New Features
 
-_None_
+- Add the possibility to configure in DerivedBuildCodeFormatter a versioning prefix instead of always defaulting to 1. [#656]
 
 ### Bug Fixes
 

lib/fastlane/plugin/wpmreleasetoolkit/versioning/formatters/derived_build_code_formatter.rb

@@ -6,9 +6,19 @@ module Versioning
       # The `DerivedBuildCodeFormatter` class is a specialized build code formatter for derived build codes.
       # It takes in an AppVersion object and derives a build code from it.
       class DerivedBuildCodeFormatter
+        # Initialize the formatter with a configurable prefix.
+        #
+        # @param [String] prefix The prefix to use for the build code. Must be a single digit (0-9), or empty string / nil.
+        #
+        def initialize(prefix: nil)
+          prefix ||= ''
+          validate_prefix!(prefix)
+          @prefix = prefix.to_s
+        end
+
         # Calculate the next derived build code.
         #
-        # This method derives a new build code from the given AppVersion object by concatenating the digit 1,
+        # This method derives a new build code from the given AppVersion object by concatenating the configured prefix,
         # the major version, the minor version, the patch version, and the build number.
         #
         # @param [AppVersion] version The AppVersion object to derive the next build code from.
@@ -19,15 +29,43 @@ class DerivedBuildCodeFormatter
         # @return [String] The formatted build code string.
         #
         def build_code(build_code = nil, version:)
-          format(
-            # 1 is appended to the beginning of the string in case there needs to be additional platforms or
-            # extensions that could then use a different digit prefix such as 2, etc.
-            '1%<major>.2i%<minor>.2i%<patch>.2i%<build_number>.2i',
+          result = format(
+            # The prefix is configurable to allow for additional platforms or
+            # extensions that could use a different digit prefix such as 2, etc.
+            '%<prefix>s%<major>.2i%<minor>.2i%<patch>.2i%<build_number>.2i',
+            prefix: @prefix,
             major: version.major,
             minor: version.minor,
             patch: version.patch,
             build_number: version.build_number
           )
+
+          result.gsub(/^0+/, '')
+        end
+
+        private
+
+        # Validates that the prefix is a valid single digit (0-9) or empty string.
+        #
+        # @param [String] prefix The prefix to validate
+        #
+        # @raise [StandardError] If the prefix is invalid
+        #
+        def validate_prefix!(prefix)
+          prefix_str = prefix.to_s
+
+          # Allow empty string
+          return if prefix_str.empty?
+
+          # Check if it's longer than 1 character
+          if prefix_str.length > 1
+            UI.user_error!("Prefix must be a single digit or empty string, got: '#{prefix_str}' (length: #{prefix_str.length})")
+          end
+
+          # Check if it's a valid integer
+          return if ('0'..'9').include?(prefix_str)
+
+          UI.user_error!("Prefix must be an integer digit (0-9) or empty string, got: '#{prefix_str}'")
         end
       end
     end

spec/derived_build_code_formatter_spec.rb

@@ -4,16 +4,118 @@
 
 describe Fastlane::Wpmreleasetoolkit::Versioning::DerivedBuildCodeFormatter do
   describe 'derives a build code from an AppVersion object' do
-    it 'derives the build code from version numbers that are single digits' do
-      version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
-      build_code_string = described_class.new.build_code(version: version)
-      expect(build_code_string.to_s).to eq('101020304')
+    context 'with default prefix (nil)' do
+      it 'derives the build code from version numbers that are single digits' do
+        version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
+        build_code_string = described_class.new.build_code(version: version)
+        expect(build_code_string.to_s).to eq('1020304')
+      end
+
+      it 'derives the build code from version numbers that are two digits' do
+        version = Fastlane::Models::AppVersion.new(12, 34, 56, 78)
+        build_code_string = described_class.new.build_code(version: version)
+        expect(build_code_string.to_s).to eq('12345678')
+      end
+    end
+
+    context 'with explicit prefix' do
+      it 'derives the build code with prefix "1"' do
+        version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
+        formatter = described_class.new(prefix: '1')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('101020304')
+      end
+
+      it 'derives the build code with prefix "2"' do
+        version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
+        formatter = described_class.new(prefix: '2')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('201020304')
+      end
+
+      it 'derives the build code with prefix "0"' do
+        version = Fastlane::Models::AppVersion.new(12, 34, 56, 78)
+        formatter = described_class.new(prefix: '0')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('12345678')
+      end
+    end
+
+    context 'with empty prefix' do
+      it 'derives the build code without prefix and trims leading zeros' do
+        version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
+        formatter = described_class.new(prefix: '')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('1020304')
+      end
+
+      it 'derives the build code without prefix for two-digit major version' do
+        version = Fastlane::Models::AppVersion.new(12, 34, 56, 78)
+        formatter = described_class.new(prefix: '')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('12345678')
+      end
+
+      it 'handles edge case with all zeros after removing leading zeros' do
+        version = Fastlane::Models::AppVersion.new(0, 0, 0, 1)
+        formatter = described_class.new(prefix: '')
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('1')
+      end
+    end
+
+    context 'with nil prefix' do
+      it 'treats nil prefix as empty string and derives build code without prefix' do
+        version = Fastlane::Models::AppVersion.new(1, 2, 3, 4)
+        formatter = described_class.new(prefix: nil)
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('1020304')
+      end
+
+      it 'treats nil prefix as empty string for two-digit major version' do
+        version = Fastlane::Models::AppVersion.new(12, 34, 56, 78)
+        formatter = described_class.new(prefix: nil)
+        build_code_string = formatter.build_code(version: version)
+        expect(build_code_string.to_s).to eq('12345678')
+      end
+    end
+  end
+
+  describe 'prefix validation' do
+    context 'with valid prefixes' do
+      it 'accepts single digits 0-9' do
+        (0..9).each do |digit|
+          expect { described_class.new(prefix: digit.to_s) }.not_to raise_error
+        end
+      end
+
+      it 'accepts empty string' do
+        expect { described_class.new(prefix: '') }.not_to raise_error
+      end
+
+      it 'accepts integer inputs' do
+        expect { described_class.new(prefix: 5) }.not_to raise_error
+      end
     end
 
-    it 'derives the build code from version numbers that are two digits' do
-      version = Fastlane::Models::AppVersion.new(12, 34, 56, 78)
-      build_code_string = described_class.new.build_code(version: version)
-      expect(build_code_string.to_s).to eq('112345678')
+    context 'with invalid prefixes' do
+      it 'rejects multi-character strings' do
+        expect { described_class.new(prefix: '12') }.to raise_error(/Prefix must be a single digit or empty string/)
+      end
+
+      it 'rejects non-numeric strings' do
+        expect { described_class.new(prefix: 'a') }.to raise_error(/Prefix must be an integer digit/)
+      end
+
+      it 'rejects numbers outside 0-9 range' do
+        expect { described_class.new(prefix: '10') }.to raise_error(/Prefix must be a single digit or empty string/)
+        expect { described_class.new(prefix: '-1') }.to raise_error(/Prefix must be a single digit or empty string/)
+      end
+
+      it 'rejects symbols and special characters' do
+        expect { described_class.new(prefix: '@') }.to raise_error(/Prefix must be an integer digit/)
+        expect { described_class.new(prefix: '#') }.to raise_error(/Prefix must be an integer digit/)
+      end
     end
   end
 end