Intellij Plugins

Main Resources:

Custom Language (basic concepts of custom language support)
Intellij Rust GitHub (A good example of a custom language plugin)
Intellij Plugin Development

Define by `plugin.xml`

IDEA

<extensions defaultExtensionNs="com.intellij">
    <!-- File-type Factory -->
    <fileType name="Feakin File"
              language="Feakin"
              implementationClass="com.feakin.intellij.FkFileType"
              fieldName="INSTANCE"
              extensions="fkl"/>
    <internalFileTemplate name="Feakin File"/>

    <!-- Parser -->
    <lang.parserDefinition language="Feakin"
                           implementationClass="com.feakin.intellij.parser.FkParserDefinition"/>

    <lang.syntaxHighlighter language="Feakin"
                            implementationClass="com.feakin.intellij.highlight.FkSyntaxHighlighter"/>

    <lang.psiStructureViewFactory language="Feakin"
                                  implementationClass="com.feakin.intellij.structure.FkStructureViewFactory"/>

    <!-- Editor -->
    <extendWordSelectionHandler implementation="com.feakin.intellij.ide.editor.FkBlockSelectionHandler"/>
    <lang.foldingBuilder language="Feakin"
                         implementationClass="com.feakin.intellij.edit.FkFoldingBuilder"/>

    <lang.commenter language="Feakin" implementationClass="com.feakin.intellij.completion.FkCommenter"/>
    <lang.braceMatcher language="Feakin" implementationClass="com.feakin.intellij.ide.FkBraceMatcher"/>


    <!-- Navigate between useDomainObject and DomainObjectDecl -->
    <indexedRootsProvider implementation="com.feakin.intellij.indexing.FkIndexableSetContributor"/>

    <stubElementTypeHolder class="com.feakin.intellij.lexer.FkElementTypes"/>

    <stubIndex implementation="com.feakin.intellij.resolve.indexes.FkNamedElementIndex"/>
    <stubIndex implementation="com.feakin.intellij.resolve.indexes.FkGotoClassIndex"/>

    <gotoSymbolContributor implementation="com.feakin.intellij.ide.navigate.FkGotoSymbolContributor"/>

    <!-- Completion -->
    <completion.contributor language="Feakin"
                            implementationClass="com.feakin.intellij.completion.FkKeywordCompletionContributor"
                            id="FkKeywordCompletionContributor"
                            order="first"/>


    <!-- Line Marker Providers -->
    <codeInsight.lineMarkerProvider language="Feakin"
                                    implementationClass="com.feakin.intellij.linemarkers.FkImplMessageProvider"/>
    <codeInsight.lineMarkerProvider language="Feakin"
                                    implementationClass="com.feakin.intellij.linemarkers.FkImplMethodProvider"/>

    <runLineMarkerContributor language="Feakin"
                              implementationClass="com.feakin.intellij.linemarkers.FkImplLineMarkerContributor"/>

    <!-- Run Configurations -->
    <configurationType implementation="com.feakin.intellij.runconfig.FkCommandConfigurationType"/>

    <programRunner implementation="com.feakin.intellij.runconfig.FkCommandRunner"/>

    <runConfigurationProducer
            implementation="com.feakin.intellij.runconfig.command.FkRunConfigurationProducer"/>

    <!-- Formatter -->
    <lang.formatter language="Feakin" implementationClass="com.feakin.intellij.formatter.FkFormattingModelBuilder"/>

    <!-- Usages Provider -->
    <lang.findUsagesProvider language="Feakin" implementationClass="com.feakin.intellij.ide.search.FkFindUsagesProvider"/>
    <findUsagesHandlerFactory implementation="com.feakin.intellij.ide.search.FkFindUsagesHandlerFactory"/>
    <usageTypeProvider implementation="com.feakin.intellij.ide.search.FkUsageTypeProvider"/>
</extensions>

Indexes with Stub

sample:

contextMapDeclaration ::= CONTEXT_MAP_KEYWORD IDENTIFIER contextMapBody
{
  implements = [
    "com.feakin.intellij.psi.FkNamedElement"
    "com.feakin.intellij.psi.FkNameIdentifierOwner"
  ]
  mixin = "com.feakin.intellij.stubs.ext.FkContextMapImplMixin"
  stubClass = "com.feakin.intellij.stubs.FkContextMapDeclStub"
  elementTypeFactory = "com.feakin.intellij.stubs.StubImplementationsKt.factory"
}

Reference

添加 Ctrl/Command + B，需要配置双向 Reference。如：

FkContextNameReferenceImpl 用于寻找对应的 FkContextDeclaration
FkContextDeclReferenceImpl 用于寻找对应的 FkContextName

配置缓存支持两种方式:

通过 stubIndex 与 BNF 中的 stubClass 配置 Stub。
通过 CachedValuesManager.getCachedValue 配置。

配置 `stubIndex` 与 BNF 中的 `stubClass` 配置 Stub

在 plugin.xml 中配置 stubIndex 配置缓存元素：

<stubIndex implementation="com.feakin.intellij.resolve.indexes.FkNamedElementIndex"/>

从 BNF 中配置 stubClass：

contextDeclaration ::= CONTEXT_KEYWORD IDENTIFIER contextBody
{
  implements = [
    "com.feakin.intellij.psi.FkNamedElement"
    "com.feakin.intellij.psi.FkNameIdentifierOwner"
    "com.feakin.intellij.psi.ext.FkMandatoryReferenceElement"
  ]
  mixin = "com.feakin.intellij.stubs.ext.FkContextDeclarationImplMixin"
  stubClass = "com.feakin.intellij.stubs.FkContextDeclarationStub"
  elementTypeFactory = "com.feakin.intellij.stubs.StubImplementationsKt.factory"
}

实现对应的配置

Custom LineMarker

自定义 LineMarker 的方式有两种：

通过 LineMarkerProvider 实现
通过 RunLineMarkerContributor 实现

<!-- line marker -->
<codeInsight.lineMarkerProvider language="Feakin"
                                implementationClass="com.feakin.intellij.linemarkers.FkImplMessageProvider"/>

<!--  producer -->
<runConfigurationProducer implementation="com.feakin.intellij.runconfig.command.FkEndpointConfigurationProducer"/>

在 Intellij Feakin 中，先创建 RunLineMarkerContributor 后，再创建 RunConfigurationProducer，如 GencodeImplConfigurationProducer。

class FkCodegenImplLineMarkerContributor : RunLineMarkerContributor() {
    override fun getInfo(element: PsiElement): Info? {
        if (element !is FkImplDeclaration) return null
        val state = GencodeImplConfigurationProducer().findConfig(listOf(element)) ?: return null

        val actions = ExecutorAction.getActions(0)
        return Info(
            AllIcons.RunConfigurations.TestState.Run,
            { state.configurationName },
            *actions
        )
    }
}

示例：

class GencodeImplConfigurationProducer : BaseLazyRunConfigurationProducer<GencodeConfig, FkImplDeclaration>() {
    override val commandName: String = "gen"

    init {
        registerConfigProvider { elements -> createConfigFor<FkImplDeclaration>(elements) }
    }

    private inline fun <reified T : FkImplDeclaration> createConfigFor(
        elements: List<PsiElement>
    ): GencodeConfig? {
        val path = elements.firstOrNull()?.containingFile?.virtualFile?.path ?: return null
        val sourceElement = elements.firstOrNull { it is T } ?: return null
        return GencodeConfig(commandName, path, sourceElement as FkImplDeclaration)
    }

    private fun registerConfigProvider(provider: (List<PsiElement>) -> GencodeConfig?) {
        runConfigProviders.add(provider)
    }
}

FkCommandLine

与 fkl_cli/src/main.rs 中的 Cli::Commands 保持一致：

class FkCommandLine(
    var path: String,
    var impl: String,
    private val subcommand: String,
    private val funcName: String = "",
)

Syntax BNF

语法解析，基于 Grammar Kit 来进行解析： https://github.com/JetBrains/Grammar-Kit

官方示例如下：

root_rule ::= rule_A rule_B rule_C rule_D                // sequence expression
rule_A ::= token | 'or_text' | "another_one"             // choice expression
rule_B ::= [ optional_token ] and_another_one?           // optional expression
rule_C ::= &required !forbidden                          // predicate expression
rule_D ::= { can_use_braces + (and_parens) * }           // grouping and repetition

// Grammar-Kit BNF syntax

{ generate=[psi="no"] }                                  // top-level global attributes
private left rule_with_modifier ::= '+'                  // rule modifiers
left rule_with_attributes ::= '?' {elementType=rule_D}   // rule attributes

private meta list ::= <<p>> (',' <<p>>) *                // meta rule with parameters
private list_usage ::= <<list rule_D>>                   // meta rule application

Feakin - 软件开发工业化 DSL