Support reading classpath from jar manifests (fix #1472)

semanticdb/metacp/src/main/scala/scala/meta/internal/metacp/Main.scala

@@ -3,6 +3,7 @@ package scala.meta.internal.metacp
 import java.nio.file._
 import java.nio.file.attribute.BasicFileAttributes
 import java.util.concurrent.ConcurrentLinkedQueue
+import java.util.jar._
 import scala.collection.JavaConverters._
 import scala.meta.cli._
 import scala.meta.internal.index._
@@ -66,7 +67,9 @@ class Main(settings: Settings, reporter: Reporter) {
     classpath.foreach { entry =>
       if (entry.isDirectory) {
         val out = AbsolutePath(Files.createTempDirectory("semanticdb"))
-        val res = convertClasspathEntry(entry, out)
+        val index = new Index
+        val res = convertClasspathEntry(entry, out, index)
+        index.save(out)
         success.compareAndSet(true, res)
         buffer.add(out)
       } else if (entry.isFile) {
@@ -78,7 +81,29 @@ class Main(settings: Settings, reporter: Reporter) {
         if (cacheEntry.toFile.exists) {
           buffer.add(cacheEntry)
         } else {
-          createCachedJar(cacheEntry)(out => convertClasspathEntry(entry, out))
+          createCachedJar(cacheEntry){ out =>
+            val index = new Index
+            def loop(entry: AbsolutePath): Boolean = {
+              var result = convertClasspathEntry(entry, out, index)
+              if (entry.isFile) {
+                val jar = new JarFile(entry.toFile)
+                val manifest = jar.getManifest
+                if (manifest != null) {
+                  val classpathAttr = manifest.getMainAttributes.getValue("Class-Path")
+                  if (classpathAttr != null) {
+                    classpathAttr.split(" ").foreach { classpathEntry =>
+                      val path = entry.toNIO.getParent.resolve(classpathEntry)
+                      result &= loop(AbsolutePath(path))
+                    }
+                  }
+                }
+              }
+              result
+            }
+            val result = loop(entry)
+            index.save(out)
+            result
+          }
         }
       }
     }
@@ -100,9 +125,8 @@ class Main(settings: Settings, reporter: Reporter) {
     }
   }
 
-  private def convertClasspathEntry(in: AbsolutePath, out: AbsolutePath): Boolean = {
+  private def convertClasspathEntry(in: AbsolutePath, out: AbsolutePath, index: Index): Boolean = {
     var success = true
-    val index = new Index
     val classpath = Classpath(in)
     classpath.visit { base =>
       new SimpleFileVisitor[Path] {
@@ -143,7 +167,6 @@ class Main(settings: Settings, reporter: Reporter) {
         }
       }
     }
-    index.save(out)
     success
   }
 

semanticdb/semanticdb3/src/main/scala/scala/meta/internal/semanticdb3/Locator.scala

@@ -45,6 +45,16 @@ object Locator {
           try fn(path, TextDocuments.parseFrom(stream))
           finally stream.close()
         }
+        val manifest = jar.getManifest
+        if (manifest != null) {
+          val classpathAttr = manifest.getMainAttributes.getValue("Class-Path")
+          if (classpathAttr != null) {
+            classpathAttr.split(" ").foreach { relativePath =>
+              val parentPath = path.toAbsolutePath.getParent
+              apply(parentPath.resolve(relativePath))(fn)
+            }
+          }
+        }
       } else if (path.toString.endsWith(".semanticdb")) {
         val stream = Files.newInputStream(path)
         try fn(path, TextDocuments.parseFrom(stream))

tests/jvm/src/test/resources/manifest.metacp

@@ -0,0 +1,23 @@
+Test.class
+----------
+
+Summary:
+Schema => SemanticDB v3
+Uri => Test.class
+Text => empty
+Language => Scala
+Symbols => 5 entries
+
+Symbols:
+_empty_. => package _empty_
+_empty_.Test. => final object Test.{+2 decls}
+  extends AnyRef
+_empty_.Test.main(Array). => method main: (args: Array[String]): Unit
+  args => _empty_.Test.main(Array).(args)
+  Array => scala.Array#
+  String => scala.Predef.String#
+  Unit => scala.Unit#
+_empty_.Test.main(Array).(args) => param args: Array[String]
+  Array => scala.Array#
+  String => scala.Predef.String#
+_root_. => package _root_

tests/jvm/src/test/resources/manifest.metap

@@ -0,0 +1,30 @@
+Test.scala
+----------
+
+Summary:
+Schema => SemanticDB v3
+Uri => Test.scala
+Text => non-empty
+Language => Scala
+Symbols => 3 entries
+Occurrences => 7 entries
+
+Symbols:
+_empty_.Test. => final object Test
+_empty_.Test.main(Array). => method main: (args: Array[String]): Unit
+  args => _empty_.Test.main(Array).(args)
+  Array => scala.Array#
+  String => scala.Predef.String#
+  Unit => scala.Unit#
+_empty_.Test.main(Array).(args) => param args: Array[String]
+  Array => scala.Array#
+  String => scala.Predef.String#
+
+Occurrences:
+[0:7..0:11): Test <= _empty_.Test.
+[1:6..1:10): main <= _empty_.Test.main(Array).
+[1:11..1:15): args <= _empty_.Test.main(Array).(args)
+[1:17..1:22): Array => scala.Array#
+[1:23..1:29): String => scala.Predef.String#
+[1:33..1:37): Unit => scala.Unit#
+[2:4..2:11): println => scala.Predef.println(Any).

tests/jvm/src/test/scala/scala/meta/tests/semanticdb/ExpectSuite.scala

@@ -61,6 +61,14 @@ class ExpectSuite extends FunSuite with DiffAssertions {
         import MetacMetacpIndexDiffExpect._
         assertNoDiff(loadObtained, loadExpected)
       }
+      test("manifest.metap") {
+        import ManifestMetap._
+        assertNoDiff(loadObtained, loadExpected)
+      }
+      test("manifest.metacp") {
+        import ManifestMetacp._
+        assertNoDiff(loadObtained, loadExpected)
+      }
     case _ =>
       ()
   }
@@ -327,6 +335,22 @@ object MetacMetacpIndexDiffExpect extends ExpectHelpers {
   }
 }
 
+object ManifestMetap extends ExpectHelpers {
+  def filename: String = "manifest.metap"
+  def loadObtained: String = {
+    val manifestJar = path.getParent.resolve("manifest.jar")
+    lowlevelSyntax(manifestJar)
+  }
+}
+
+object ManifestMetacp extends ExpectHelpers {
+  def filename: String = "manifest.metacp"
+  def loadObtained: String = {
+    val manifestJar = path.getParent.resolve("manifest.jar")
+    lowlevelSyntax(decompiledPath(manifestJar))
+  }
+}
+
 // To save the current behavior, run `sbt save-expect`.
 object SaveExpectTest {
   def main(args: Array[String]): Unit = {
@@ -339,5 +363,7 @@ object SaveExpectTest {
     MetacOwnersExpect.saveExpected(MetacOwnersExpect.loadObtained)
     MetacMetacpExpectDiffExpect.saveExpected(MetacMetacpExpectDiffExpect.loadObtained)
     MetacMetacpIndexDiffExpect.saveExpected(MetacMetacpIndexDiffExpect.loadObtained)
+    ManifestMetap.saveExpected(ManifestMetap.loadObtained)
+    ManifestMetacp.saveExpected(ManifestMetacp.loadObtained)
   }
 }