Fix trailing whitespace in output functions

lib/maven.sh

@@ -389,7 +389,7 @@ function maven::install_settings_xml() {
 
 				Check that the URL in your MAVEN_SETTINGS_URL environment
 				variable is correct and publicly accessible. If the settings file
-				is not needed, you can remove the MAVEN_SETTINGS_URL environment variable 
+				is not needed, you can remove the MAVEN_SETTINGS_URL environment variable
 				to use default Maven settings.
 
 				Learn more about Maven settings configuration:

lib/output.sh

@@ -4,6 +4,7 @@ ANSI_BLUE='\033[1;34m'
 ANSI_RED='\033[1;31m'
 ANSI_YELLOW='\033[1;33m'
 ANSI_RESET='\033[0m'
+MESSAGE_INDENTATION='     '
 
 # Output a single line step message to stdout.
 #
@@ -36,10 +37,15 @@ function output::indent() {
 # EOF
 # ```
 function output::notice() {
-	local line
+	local line indentation
 	echo >&2
 	while IFS= read -r line; do
-		echo -e "${ANSI_BLUE} !     ${line}${ANSI_RESET}" >&2
+		indentation=""
+		if [[ -n "${line}" ]]; then
+			indentation="${MESSAGE_INDENTATION}"
+		fi
+
+		echo -e "${ANSI_BLUE} !${indentation}${line}${ANSI_RESET}" >&2
 	done
 	echo >&2
 }
@@ -55,10 +61,15 @@ function output::notice() {
 # EOF
 # ```
 function output::warning() {
-	local line
+	local line indentation
 	echo >&2
 	while IFS= read -r line; do
-		echo -e "${ANSI_YELLOW} !     ${line}${ANSI_RESET}" >&2
+		indentation=""
+		if [[ -n "${line}" ]]; then
+			indentation="${MESSAGE_INDENTATION}"
+		fi
+
+		echo -e "${ANSI_YELLOW} !${indentation}${line}${ANSI_RESET}" >&2
 	done
 	echo >&2
 }
@@ -74,10 +85,15 @@ function output::warning() {
 # EOF
 # ```
 function output::error() {
-	local line
+	local line indentation
 	echo >&2
 	while IFS= read -r line; do
-		echo -e "${ANSI_RED} !     ${line}${ANSI_RESET}" >&2
+		indentation=""
+		if [[ -n "${line}" ]]; then
+			indentation="${MESSAGE_INDENTATION}"
+		fi
+
+		echo -e "${ANSI_RED} !${indentation}${line}${ANSI_RESET}" >&2
 	done
 	echo >&2
 }

test/spec/detection_spec.rb

@@ -9,28 +9,28 @@
       expect(clean_output(app.output)).to include(<<~OUTPUT)
         remote:  !     Error: Your app is configured to use the Java buildpack,
         remote:  !     but we couldn't find any supported Java project files.
-        remote:  !     
+        remote:  !
         remote:  !     The Java buildpack only supports Maven projects. It requires a pom.xml
         remote:  !     file or other supported POM format in the root directory of your source code.
-        remote:  !     
+        remote:  !
         remote:  !     Supported POM formats: pom.xml, pom.atom, pom.clj, pom.groovy, pom.rb, pom.scala, pom.yaml, pom.yml
-        remote:  !     
+        remote:  !
         remote:  !     IMPORTANT: If your Java project uses a different build tool:
         remote:  !     - For Gradle projects, use the heroku/gradle buildpack instead
         remote:  !     - For sbt projects (including Play! Framework), use the heroku/scala buildpack instead
-        remote:  !     
+        remote:  !
         remote:  !     Currently the root directory of your app contains:
-        remote:  !     
+        remote:  !
         remote:  !     README.md
-        remote:  !     
+        remote:  !
         remote:  !     If your app already has a POM file, check that it:
-        remote:  !     
+        remote:  !
         remote:  !     1. Is in the top level directory (not a subdirectory).
         remote:  !     2. Has the correct spelling (the filenames are case-sensitive).
         remote:  !     3. Isn't listed in '.gitignore' or '.slugignore'.
         remote:  !     4. Has been added to the Git repository using 'git add --all'
         remote:  !        and then committed using 'git commit'.
-        remote:  !     
+        remote:  !
         remote:  !     For help with using Java on Heroku, see:
         remote:  !     https://devcenter.heroku.com/articles/java-support
       OUTPUT

test/spec/misc_spec.rb

@@ -72,26 +72,26 @@
         remote:        \\[ERROR\\] 
         remote:        \\[ERROR\\] For more information about the errors and possible solutions, please read the following articles:
         remote:        \\[ERROR\\] \\[Help 1\\] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
-        remote: 
+        remote:
         remote:  !     Error: Maven build failed.
-        remote:  !     
+        remote:  !
         remote:  !     An error occurred during the Maven build process. This usually
         remote:  !     indicates an issue with your application's dependencies, configuration,
         remote:  !     or source code.
-        remote:  !     
+        remote:  !
         remote:  !     First, check the build output above for specific error messages
         remote:  !     from Maven that might indicate what went wrong. Common issues include:
-        remote:  !     
+        remote:  !
         remote:  !     - Missing or incompatible dependencies in your POM
         remote:  !     - Compilation errors in your application source code
         remote:  !     - Test failures \\(if tests are enabled during the build\\)
         remote:  !     - Invalid Maven configuration or settings
         remote:  !     - Using an incompatible OpenJDK version for your project
-        remote:  !     
+        remote:  !
         remote:  !     If you're unable to determine the cause from the Maven output,
         remote:  !     try building your application locally with the same Maven command
         remote:  !     to reproduce and debug the issue.
-        remote: 
+        remote:
         remote:  !     Push rejected, failed to compile Java app.
       REGEX
     end
@@ -108,21 +108,21 @@
       expect(app.output).to include('[INFO] BUILD SUCCESS')
       expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX, Regexp::MULTILINE))
         remote:  !     Warning: Maven Wrapper script found without properties file\\.
-        remote:  !     
+        remote:  !
         remote:  !     Found mvnw script but missing \\.mvn/wrapper/maven-wrapper\\.properties\\.
         remote:  !     The Maven Wrapper requires both files to function properly\\.
-        remote:  !     
+        remote:  !
         remote:  !     To fix this issue, run this command in your project directory
         remote:  !     locally and commit the generated files:
         remote:  !     \\$ mvn wrapper:wrapper
-        remote:  !     
+        remote:  !
         remote:  !     Alternatively, if you don't want to use Maven Wrapper, you can
         remote:  !     delete the mvnw file from your project, though the usage of the
         remote:  !     Maven Wrapper is strongly recommended\\.
-        remote:  !     
+        remote:  !
         remote:  !     IMPORTANT: This warning will become an error in a future version
         remote:  !     of this buildpack\\. Please fix this issue as soon as possible\\.
-        remote:  !     
+        remote:  !
         remote:  !     For more information about Maven Wrapper, see:
         remote:  !     https://maven\\.apache\\.org/tools/wrapper/
         remote:  !     https://devcenter\\.heroku\\.com/articles/java-support#specifying-a-maven-version

test/spec/settings_xml_spec.rb

@@ -18,22 +18,22 @@
     app.deploy do
       expect(clean_output(app.output)).to include(<<~OUTPUT)
         remote:  !     Error: Unable to download Maven settings.xml.
-        remote:  !     
+        remote:  !
         remote:  !     An error occurred while downloading the Maven settings file from:
         remote:  !     #{SETTINGS_XML_URL_404}
-        remote:  !     
+        remote:  !
         remote:  !     In some cases, this happens due to a temporary issue with
         remote:  !     the network connection or server, or because the URL is
         remote:  !     inaccessible or requires authentication.
-        remote:  !     
+        remote:  !
         remote:  !     Check that the URL in your MAVEN_SETTINGS_URL environment
         remote:  !     variable is correct and publicly accessible. If the settings file
-        remote:  !     is not needed, you can remove the MAVEN_SETTINGS_URL environment variable 
+        remote:  !     is not needed, you can remove the MAVEN_SETTINGS_URL environment variable
         remote:  !     to use default Maven settings.
-        remote:  !     
+        remote:  !
         remote:  !     Learn more about Maven settings configuration:
         remote:  !     https://devcenter.heroku.com/articles/using-a-custom-maven-settings-xml
-        remote: 
+        remote:
         remote:  !     Push rejected, failed to compile Java app.
       OUTPUT
     end
@@ -147,12 +147,12 @@
       app.deploy do
         expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX, Regexp::MULTILINE))
           remote:  !     Warning: Using existing settings\\.xml file\\.
-          remote:  !     
+          remote:  !
           remote:  !     A settings\\.xml file already exists at .*\\.m2/settings\\.xml\\.
           remote:  !     However, the MAVEN_SETTINGS_PATH environment variable is set, which
           remote:  !     would normally be used as the settings\\.xml configuration\\. The existing
           remote:  !     file will be used\\.
-          remote:  !     
+          remote:  !
           remote:  !     If you intended to use the settings from MAVEN_SETTINGS_PATH instead,
           remote:  !     remove the existing settings\\.xml file at .*\\.m2/settings\\.xml\\.
         REGEX
@@ -180,12 +180,12 @@
       app.deploy do
         expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX, Regexp::MULTILINE))
           remote:  !     Warning: Using existing settings\\.xml file\\.
-          remote:  !     
+          remote:  !
           remote:  !     A settings\\.xml file already exists at .*\\.m2/settings\\.xml\\.
           remote:  !     However, the MAVEN_SETTINGS_URL environment variable is set, which
           remote:  !     would normally be used as the settings\\.xml configuration\\. The existing
           remote:  !     file will be used\\.
-          remote:  !     
+          remote:  !
           remote:  !     If you intended to use the settings from MAVEN_SETTINGS_URL instead,
           remote:  !     remove the existing settings\\.xml file at .*\\.m2/settings\\.xml\\.
         REGEX
@@ -215,12 +215,12 @@
       app.deploy do
         expect(clean_output(app.output)).to match(Regexp.new(<<~REGEX, Regexp::MULTILINE))
           remote:  !     Warning: Using existing settings\\.xml file\\.
-          remote:  !     
+          remote:  !
           remote:  !     A settings\\.xml file already exists at .*\\.m2/settings\\.xml\\.
           remote:  !     However, a settings\\.xml file was also found in the project directory,
           remote:  !     which would normally be used as the settings\\.xml configuration\\. The
           remote:  !     existing file will be used\\.
-          remote:  !     
+          remote:  !
           remote:  !     If you intended to use the settings from your project directory instead,
           remote:  !     remove the existing settings\\.xml file at .*\\.m2/settings\\.xml\\.
         REGEX

test/spec/spec_helper.rb

@@ -58,4 +58,6 @@ def clean_output(output)
     .gsub(/ {8}(?=\R)/, '')
     # Remove ANSI colour codes used in buildpack output (e.g. error messages).
     .gsub(/\e\[[0-9;]+m/, '')
+    # Remove trailing space from empty "remote: " lines added by Heroku
+    .gsub(/^remote: $/, 'remote:')
 end

test/spec/versions_spec.rb

@@ -37,32 +37,32 @@
     app.deploy do
       expect(clean_output(app.output)).to include(<<~OUTPUT)
         remote: -----> Installing Maven #{UNKNOWN_MAVEN_VERSION}...
-        remote: 
+        remote:
         remote:  !     Error: The requested Maven version isn't available.
-        remote:  !     
+        remote:  !
         remote:  !     Your app's system.properties file specifies a Maven version
         remote:  !     of #{UNKNOWN_MAVEN_VERSION}, however, we couldn't find that version in the
         remote:  !     Maven repository.
-        remote:  !     
+        remote:  !
         remote:  !     Check that this Maven version has been released upstream:
         remote:  !     https://maven.apache.org/docs/history.html
-        remote:  !     
+        remote:  !
         remote:  !     If it has, make sure that you are using the latest version
         remote:  !     of this buildpack, and haven't pinned to an older release:
         remote:  !     https://devcenter.heroku.com/articles/managing-buildpacks#view-your-buildpacks
         remote:  !     https://devcenter.heroku.com/articles/managing-buildpacks#classic-buildpacks-references
-        remote:  !     
+        remote:  !
         remote:  !     We also strongly recommend using the Maven Wrapper instead of
         remote:  !     pinning to an exact Maven version such as #{UNKNOWN_MAVEN_VERSION}.
         remote:  !     Remove the maven.version property from your system.properties file
         remote:  !     and set up Maven Wrapper in your project, which will automatically
         remote:  !     download and use the correct Maven version.
-        remote:  !     
+        remote:  !
         remote:  !     Learn more about Maven Wrapper:
         remote:  !     https://maven.apache.org/wrapper/
-        remote:  !     
+        remote:  !
         remote:  !     The default supported version is #{DEFAULT_MAVEN_VERSION}.
-        remote: 
+        remote:
         remote:  !     Push rejected, failed to compile Java app.
       OUTPUT
     end
@@ -93,32 +93,32 @@
     app.deploy do
       expect(clean_output(app.output)).to include(<<~OUTPUT)
         remote: -----> Installing Maven #{UNKNOWN_MAVEN_VERSION}...
-        remote: 
+        remote:
         remote:  !     Error: The requested Maven version isn't available.
-        remote:  !     
+        remote:  !
         remote:  !     Your app's system.properties file specifies a Maven version
         remote:  !     of #{UNKNOWN_MAVEN_VERSION}, however, we couldn't find that version in the
         remote:  !     Maven repository.
-        remote:  !     
+        remote:  !
         remote:  !     Check that this Maven version has been released upstream:
         remote:  !     https://maven.apache.org/docs/history.html
-        remote:  !     
+        remote:  !
         remote:  !     If it has, make sure that you are using the latest version
         remote:  !     of this buildpack, and haven't pinned to an older release:
         remote:  !     https://devcenter.heroku.com/articles/managing-buildpacks#view-your-buildpacks
         remote:  !     https://devcenter.heroku.com/articles/managing-buildpacks#classic-buildpacks-references
-        remote:  !     
+        remote:  !
         remote:  !     We also strongly recommend using the Maven Wrapper instead of
         remote:  !     pinning to an exact Maven version such as #{UNKNOWN_MAVEN_VERSION}.
         remote:  !     Remove the maven.version property from your system.properties file
         remote:  !     and set up Maven Wrapper in your project, which will automatically
         remote:  !     download and use the correct Maven version.
-        remote:  !     
+        remote:  !
         remote:  !     Learn more about Maven Wrapper:
         remote:  !     https://maven.apache.org/wrapper/
-        remote:  !     
+        remote:  !
         remote:  !     The default supported version is #{DEFAULT_MAVEN_VERSION}.
-        remote: 
+        remote:
         remote:  !     Push rejected, failed to compile Java app.
       OUTPUT
     end