fix: handle more kinds of dependency declarations on properties.

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

@@ -169,11 +169,7 @@ public class DependencyExtractor(
           val maybeProjectType = newLeaf.primaryExpression().text
           if (maybeProjectType == "project") {
             type = DependencyDeclaration.Type.PROJECT
-            identifier = quoted(
-              newLeaf.postfixUnarySuffix().single()
-                .callSuffix()
-                .valueArguments().valueArgument().single()
-            ).asSimpleIdentifier()
+            identifier = newLeaf.findIdentifier()
           } else {
             // e.g., `libs.kotlinGradleBom` ("libs" is the primaryExpression)
             identifier = newLeaf.text.asSimpleIdentifier()
@@ -188,6 +184,10 @@ public class DependencyExtractor(
       identifier = leaf.text.asSimpleIdentifier()
     }
 
+    if (identifier == null && leaf is PostfixUnaryExpressionContext) {
+      identifier = leaf.findIdentifier()
+    }
+
     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}")
@@ -248,6 +248,10 @@ public class DependencyExtractor(
           return Identifier(path = identifier, explicitPath = true)
         }
       }
+
+      (singleArg.leafRule() as? SimpleIdentifierContext)?.Identifier()?.text.asSimpleIdentifier()?.let {
+        return it
+      }
     }
 
     // Unclear what this would be, bail

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

@@ -62,6 +62,40 @@ internal class DependencyExtractorTest {
         capability = Capability.DEFAULT,
         type = Type.MODULE,
       ),
+      /*
+       * This case might look like this in a build script:
+       * ```
+       * val gav = "g:a:v"
+       * dependencies {
+       *   api(platform(gav))
+       * }
+       * ```
+       */
+      TestCase(
+        displayName = "extracted string coordinates for a platform",
+        fullText = "api(platform(gav))",
+        configuration = "api",
+        identifier = "gav",
+        capability = Capability.PLATFORM,
+        type = Type.MODULE,
+      ),
+      /*
+       * This case might look like this in a build script:
+       * ```
+       * val proj = ":project"
+       * dependencies {
+       *   api(platform(project(proj)))
+       * }
+       * ```
+       */
+      TestCase(
+        displayName = "extracted string coordinates for a platform on a project",
+        fullText = "api(platform(project(proj)))",
+        configuration = "api",
+        identifier = "proj",
+        capability = Capability.PLATFORM,
+        type = Type.PROJECT,
+      ),
       TestCase(
         displayName = "version catalog accessor",
         fullText = "implementation(libs.gAV)",