feat: support parsing more complex dependency declarations.

core/src/main/kotlin/cash/grammar/kotlindsl/model/DependencyDeclaration.kt

@@ -35,12 +35,19 @@ package cash.grammar.kotlindsl.model
  * [ModuleDependency](https://docs.gradle.org/current/javadoc/org/gradle/api/artifacts/ModuleDependency.html).
  */
 public data class DependencyDeclaration(
+  // This is the configuration (required) this dependency is declared on
   val configuration: String,
   val identifier: Identifier,
   val capability: Capability,
   val type: Type,
   val fullText: String,
+  // This is the configuration (optional) that the producer publishes on
+  val producerConfiguration: String? = null,
+  val classifier: String? = null,
+  val ext: String? = null,
   val precedingComment: String? = null,
+  // A complex declaration will use the `implementation(name = ..., group = ..., [etc])` form
+  val isComplex: Boolean = false,
 ) {
 
   public data class Identifier @JvmOverloads constructor(
@@ -49,6 +56,12 @@ public data class DependencyDeclaration(
     public val explicitPath: Boolean = false,
   ) {
 
+    // A helper class for use during parsing
+    internal class IdentifierElement(
+      val value: String,
+      val isStringLiteral: Boolean,
+    )
+
     /**
      * ```
      * 1. "g:a:v"

core/src/main/kotlin/cash/grammar/kotlindsl/utils/DependencyExtractor.kt

@@ -1,9 +1,13 @@
 package cash.grammar.kotlindsl.utils
 
-import cash.grammar.kotlindsl.model.*
+import cash.grammar.kotlindsl.model.DependencyDeclaration
 import cash.grammar.kotlindsl.model.DependencyDeclaration.Capability
 import cash.grammar.kotlindsl.model.DependencyDeclaration.Identifier
 import cash.grammar.kotlindsl.model.DependencyDeclaration.Identifier.Companion.asSimpleIdentifier
+import cash.grammar.kotlindsl.model.DependencyDeclaration.Identifier.IdentifierElement
+import cash.grammar.kotlindsl.model.DependencyDeclarationElement
+import cash.grammar.kotlindsl.model.DependencyElement
+import cash.grammar.kotlindsl.model.NonDependencyDeclarationElement
 import cash.grammar.kotlindsl.model.gradle.DependencyContainer
 import cash.grammar.kotlindsl.utils.Blocks.isBuildscript
 import cash.grammar.kotlindsl.utils.Blocks.isDependencies
@@ -13,6 +17,7 @@ import cash.grammar.kotlindsl.utils.Context.literalText
 import com.squareup.cash.grammar.KotlinParser.NamedBlockContext
 import com.squareup.cash.grammar.KotlinParser.PostfixUnaryExpressionContext
 import com.squareup.cash.grammar.KotlinParser.SimpleIdentifierContext
+import com.squareup.cash.grammar.KotlinParser.ValueArgumentContext
 import org.antlr.v4.runtime.CharStream
 import org.antlr.v4.runtime.CommonTokenStream
 import org.antlr.v4.runtime.ParserRuleContext
@@ -23,6 +28,13 @@ public class DependencyExtractor(
   indent: String,
 ) {
 
+  private enum class DeclarationDetectionResult {
+    DECLARATION_NORMAL,  // like `implementation("...") { ... }`
+    DECLARATION_COMPLEX, // like `implementation(group = "", name = "", version = "", configuration = "", classifier = "", ext = "") { ... }`
+    STATEMENT,           // not an obvious dependency declaration
+    ;
+  }
+
   private val comments = Comments(tokens, indent)
 
   public fun onEnterBlock() {
@@ -47,8 +59,18 @@ public class DependencyExtractor(
     return statements
       .map { stmt ->
         val leaf = stmt.leafRule()
-        if (leaf is PostfixUnaryExpressionContext && leaf.isDependencyDeclaration()) {
-          DependencyDeclarationElement(parseDependencyDeclaration(leaf), stmt)
+        if (leaf is PostfixUnaryExpressionContext) {
+          when (leaf.isDependencyDeclaration()) {
+            DeclarationDetectionResult.DECLARATION_NORMAL -> {
+              DependencyDeclarationElement(parseDependencyDeclaration(leaf), stmt)
+            }
+
+            DeclarationDetectionResult.DECLARATION_COMPLEX -> {
+              DependencyDeclarationElement(parseComplexDependencyDeclaration(leaf), stmt)
+            }
+
+            else -> NonDependencyDeclarationElement(stmt)
+          }
         } else {
           NonDependencyDeclarationElement(stmt)
         }
@@ -76,7 +98,8 @@ public class DependencyExtractor(
 
     return statements.mapNotNull { statement ->
       val leaf = statement.leafRule() as? PostfixUnaryExpressionContext ?: return@mapNotNull null
-      if (!leaf.isDependencyDeclaration()) return@mapNotNull null
+      // TODO(tsr): handle complex declaration?
+      if (leaf.isDependencyDeclaration() != DeclarationDetectionResult.DECLARATION_NORMAL) return@mapNotNull null
       DependencyDeclarationElement(parseDependencyDeclaration(leaf), statement)
     }.asContainer()
   }
@@ -91,6 +114,11 @@ public class DependencyExtractor(
       && blockStack[1].isBuildscript
   }
 
+  /**
+   * Parses a [DependencyDeclaration] out of a [declaration] in source code.
+   *
+   * @see [parseComplexDependencyDeclaration]
+   */
   private fun parseDependencyDeclaration(declaration: PostfixUnaryExpressionContext): DependencyDeclaration {
     // This is everything after the configuration, including optionally a trailing lambda
     val rawDependency = declaration.postfixUnarySuffix().single().callSuffix()
@@ -202,6 +230,89 @@ public class DependencyExtractor(
     )
   }
 
+  /**
+   * Given a declaration like
+   * ```
+   * implementation(group = "...", name = "...", version = ..., configuration = "...", classifier = "...", ext = "...") {
+   *   ...
+   * }
+   * ```
+   * ...where `version` can be either a String literal or a complex expression, for example
+   * ```
+   * version = "1.0" // 1
+   * version = libs.versions.foo.get() // 2
+   * ```
+   *
+   * Will return a [DependencyDeclaration].
+   *
+   * TODO(tsr): this method can only handle the simplest case of a "complex declaration" on a module dependency with
+   *  the default capability.
+   *
+   * @see [parseDependencyDeclaration]
+   */
+  private fun parseComplexDependencyDeclaration(declaration: PostfixUnaryExpressionContext): DependencyDeclaration {
+    // This is everything after the configuration, including optionally a trailing lambda
+    val rawDependency = declaration.postfixUnarySuffix().single().callSuffix()
+    val args = rawDependency.valueArguments().valueArgument()
+
+    // e.g., `classpath`, `implementation`, etc.
+    val configuration = declaration.primaryExpression().text
+    val capability = Capability.DEFAULT
+    val type = DependencyDeclaration.Type.MODULE
+
+    fun List<ValueArgumentContext>.valueOf(name: String): IdentifierElement? {
+      val expression = firstOrNull { it.simpleIdentifier().text == name }?.expression()
+      var value = expression?.let { literalText(it) }
+      val isString = value != null
+
+      // only `version` is permitted to not be a string literal
+      if (value == null && name == "version") {
+        value = expression?.text
+      }
+
+      return value?.let {
+        IdentifierElement(
+          value = value,
+          isStringLiteral = isString,
+        )
+      }
+    }
+
+    val group = args.valueOf("group") ?: error("missing group")
+    val name = args.valueOf("name") ?: error("missing name")
+    val version = args.valueOf("version")
+    val classifier = args.valueOf("classifier")
+    val ext = args.valueOf("ext")
+    val producerConfiguration = args.valueOf("configuration")
+
+    val identifier = if (version == null) {
+      "\"${group.value}:${name.value}\"".asSimpleIdentifier()
+    } else if (version.isStringLiteral) {
+      "\"${group.value}:${name.value}:${version.value}\"".asSimpleIdentifier()
+    } else {
+      // version is non-null and a complex expression (not a string literal)
+      "\"${group.value}:${name.value}:\${${version.value}}\"".asSimpleIdentifier()
+    }
+
+    val precedingComment = comments.getCommentsToLeft(declaration)
+    val fullText = declaration.fullText(input)
+      ?: error("Could not determine 'full text' of dependency declaration. Failed to parse expression:\n  ${declaration.text}")
+
+    return DependencyDeclaration(
+      configuration = configuration,
+      identifier = identifier
+        ?: error("Could not determine dependency identifier. Failed to parse expression:\n  `$fullText`"),
+      capability = capability,
+      type = type.or(identifier),
+      producerConfiguration = producerConfiguration?.value,
+      classifier = classifier?.value,
+      ext = ext?.value,
+      fullText = fullText,
+      precedingComment = precedingComment,
+      isComplex = true,
+    )
+  }
+
   /**
    * The quotation marks are an important part of how the dependency is declared. Is it
    * ```
@@ -214,13 +325,46 @@ public class DependencyExtractor(
     return literalText(ctx)?.let { "\"$it\"" }
   }
 
-  private fun PostfixUnaryExpressionContext.isDependencyDeclaration(): Boolean {
+  private fun PostfixUnaryExpressionContext.isDependencyDeclaration(): DeclarationDetectionResult {
     // This is everything after the configuration, including optionally a trailing lambda
-    val rawDependency = this.postfixUnarySuffix().single().callSuffix()
+    val rawDependency = postfixUnarySuffix().single().callSuffix()
     val args = rawDependency.valueArguments().valueArgument()
 
     // If there are more than one argument, it's a function call, not a dependency declaration
-    return args.size <= 1
+    return if (args.size <= 1) {
+      DeclarationDetectionResult.DECLARATION_NORMAL
+    } else if (looksLikeComplexDeclaration(args)) {
+      DeclarationDetectionResult.DECLARATION_COMPLEX
+    } else {
+      DeclarationDetectionResult.STATEMENT
+    }
+  }
+
+  /**
+   * For example:
+   * ```
+   * implementation(group = "", name = "", version = "", configuration = "", classifier = "", ext = "") { ... }
+   * ```
+   */
+  private fun looksLikeComplexDeclaration(argContexts: List<ValueArgumentContext>): Boolean {
+    // max number of args
+    if (argContexts.size > 6) return false
+    val args = argContexts.mapNotNull { it.simpleIdentifier()?.text }
+
+    // Then some of our args don't match the expected form of `name = value`
+    if (args.size != argContexts.size) return false
+
+    val requiredArgs = setOf("group", "name")
+
+    // `group` and `name` are required arguments
+    if (!args.containsAll(requiredArgs)) return false
+
+    val validArgNames = listOf("group", "name", "version", "configuration", "classifier", "ext")
+    // We need a mutable list because each name can only be used once.
+    val argNames = validArgNames.toMutableList()
+
+    // Every arg in args must have a match in validArgNames AND `group` and `name` are required arguments
+    return args.all { argName -> argNames.remove(argName) }
   }
 
   private fun PostfixUnaryExpressionContext.findIdentifier(): Identifier? {

core/src/test/kotlin/cash/grammar/kotlindsl/utils/DependencyExtractorTest.kt

@@ -40,7 +40,7 @@ internal class DependencyExtractorTest {
         add("extraImplementation", libs.fortyTwo)
         
         val complex = "a:complex:${'$'}expression"
-        
+                
         if (org.apache.tools.ant.taskdefs.condition.Os.isArch("aarch64")) {
           // Multi-line comment about why we're
           // doing this.
@@ -77,6 +77,51 @@ internal class DependencyExtractorTest {
     )
   }
 
+  @Test fun `can parse complex declarations`() {
+    // Given
+    val buildScript = """
+      dependencies {
+        implementation(group = "com.foo", name = "bar", version = libs.versions.bar.get(), configuration = "ohno", classifier = "classified", ext = "why") {
+          isTransitive = false
+        }
+        
+        api(group = "com.foo", name = "bar", version = "1.0")
+      }
+    """.trimIndent()
+
+    // When
+    val scriptListener = listenerFor(buildScript)
+
+    // Then
+    assertThat(scriptListener.dependencyDeclarations).containsExactly(
+      DependencyDeclaration(
+        configuration = "implementation",
+        identifier = "\"com.foo:bar:\${libs.versions.bar.get()}\"".asSimpleIdentifier()!!,
+        capability = DependencyDeclaration.Capability.DEFAULT,
+        type = DependencyDeclaration.Type.MODULE,
+        producerConfiguration = "ohno",
+        classifier = "classified",
+        ext = "why",
+        // The whitespace below is a bit wonky, but it's an artifact of the test fixture, not the API.
+        fullText = """
+            implementation(group = "com.foo", name = "bar", version = libs.versions.bar.get(), configuration = "ohno", classifier = "classified", ext = "why") {
+                isTransitive = false
+              }
+          """.trimIndent(),
+        precedingComment = null,
+        isComplex = true,
+      ),
+      DependencyDeclaration(
+        configuration = "api",
+        identifier = "\"com.foo:bar:1.0\"".asSimpleIdentifier()!!,
+        capability = Capability.DEFAULT,
+        type = Type.MODULE,
+        fullText = """api(group = "com.foo", name = "bar", version = "1.0")""",
+        isComplex = true,
+      )
+    )
+  }
+
   private fun listenerFor(buildScript: String): TestListener {
     return Parser(
       file = buildScript,