Add new language support

To add support for a new language you have to do the following steps:

• Check out the source code of this plugin
• Open IDEA and install the following IDEA plugins:
  • PsiViewer
  • Lombok
• Open this project in IDEA and go to the project settings
  • Set up the project SDK according to this site (you can skip all steps after Select 1.8 as the default Java SDK)
  • The Intellij Platform Plugin SDK should use a JDK 8
• now you have two options:
  • SHORT WAY (disable support for all unnecessary languages):

    • Open File → Settings and go to Build, Execution, Deployment → Compiler → Excluded

    • Exclude all sub directories of src/de/endrullis/idea/postfixtemplates/languages/ except java

    • Open the file plugin.xml and go to the line

      <codeInsight.template.postfixTemplateProvider language="JavaScript"

      and comment out all postfixTemplateProvider for languages other than Java.

  • LONG WAY (set up the full environment):

    • Install the following IDEA plugins:

      • Scala
      • Dart
      • Python
      • PHP
      • Rust

    • Close IDEA

    • Open the file $HOME/.IntelliJIdea2018.3/config/options/jdk.table (path might be different for you depending on your OS and your IDEA version, see here) and search for the Intellij Platform SDK you are using (e.g. "IntelliJ IDEA IU-183.4588.61")

    • Locate the classpath tag and the root child tag and append the following lines inside the root tag:

        <root url="jar://$APPLICATION_HOME_DIR$/plugins/JavaScriptLanguage/lib/javascript-openapi.jar!/" type="simple" />
        <root url="jar://$APPLICATION_HOME_DIR$/plugins/JavaScriptLanguage/lib/JavaScriptLanguage.jar!/" type="simple" />
        <root url="jar://$APPLICATION_HOME_DIR$/plugins/Kotlin/lib/kotlin-plugin.jar!/" type="simple" />
        <root url="jar://$APPLICATION_HOME_DIR$/plugins/Groovy/lib/Groovy.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/php/lib/php-openapi.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/python/lib/python.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/intellij-rust/lib/intellij-rust-0.2.0.2112-183.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/Dart/lib/Dart.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/Scala/lib/scalaUltimate.jar!/" type="simple" />
        <root url="jar://$APPLICATION_PLUGINS_DIR$/Scala/lib/scala-library.jar!/" type="simple" />
      

    • Start IDEA again

• run the plugin project in IDEA once to test if the configuration works fine
• Create the necessary folders and files for the new language (in the following I use the variables $languageId and $language as placeholders in path names and file names, whereas $language denotes the real name, e.g. SQL, and $languageId denotes just an ID for the language (usually the lower case variant), e.g. sql):

  • create the folder src/de/endrullis/idea/postfixtemplates/languages/$languageId

  • copy all classes from src/de/endrullis/idea/postfixtemplates/languages/javascript to src/de/endrullis/idea/postfixtemplates/languages/$languageId by replacing each JavaScript occurrence by your language name or camel case language name (e.g. Sql)

  • add your class ${language}Lang to the list SupportedLanguages.supportedLanguages.

  • create the folder resources/postfixTemplates/Custom${language}StringPostfixTemplate

  • copy all files from resources/postfixTemplates/CustomJavaScriptStringPostfixTemplate to resources/postfixTemplates/Custom${language}StringPostfixTemplate

  • add the following lines to the plugin.xml:

    <codeInsight.template.postfixTemplateProvider language="$language"
                                                  implementationClass="de.endrullis.idea.postfixtemplates.languages.$languageId.${language}PostfixTemplateProvider"/>
    

• Start the plugin and test if it works by opening any $language file and pressing Shift+Alt+P. If you are offered to create a new template file, the file type detection works.
• Go back to a $language file and try to apply the .example template on any expression. If it works all basic steps are done and you have an untyped postfix template support for $language.
• You can now try to add a typed postfix template support. I suggest you to install the PsiViewer plugin to analyse the different expression types in IDEA.