IDE: Support multi-project rename

Fixes scala#4994

Author: Duhemm

language-server/src/dotty/tools/languageserver/DottyLanguageServer.scala

@@ -380,18 +380,24 @@ class DottyLanguageServer extends LanguageServer
                 List(
                   RENAME_OVERRIDDEN    -> (() => (Include.all, syms.flatMap(s => s :: s.allOverriddenSymbols.toList))),
                   RENAME_NO_OVERRIDDEN -> (() => (Include.all.except(Include.overridden), syms)))
-              ).get.getOrElse((Include.empty, List.empty[Symbol]))
+              ).get.getOrElse((Include.empty, Nil))
             } else {
               (Include.all, syms)
             }
 
           val names = allSymbols.map(_.name.sourceModuleName).toSet
-          val trees = names.flatMap(name => driver.allTreesContaining(name.toString)).toList
-          allSymbols.flatMap { sym =>
-            Interactive.findTreesMatching(trees,
-              include,
-              sym,
-              t => names.exists(Interactive.sameName(t.name, _)))
+          val definitions = Interactive.findDefinitions(allSymbols, driver, include.isOverridden, includeExternal = true)
+          val perProjectInfo = inProjectsSeeing(driver, definitions, allSymbols)
+
+          perProjectInfo.flatMap { (remoteDriver, ctx, definitions) =>
+            definitions.flatMap { definition =>
+              val name = definition.name(ctx).sourceModuleName.toString
+              val trees = remoteDriver.sourceTreesContaining(name)(ctx)
+              Interactive.findTreesMatching(trees,
+                                            include,
+                                            definition,
+                                            t => names.exists(Interactive.sameName(t.name, _)))(ctx)
+            }
           }
       }
 

language-server/test/dotty/tools/languageserver/RenameTest.scala

@@ -236,6 +236,85 @@ class RenameTest {
 
   }
 
+  @Test def renameValMultiProject: Unit = {
+    def testRename(m: CodeMarker, expectations: Set[CodeRange]) = {
+      val p0 = Project.withSources(
+        code"""object A { val ${m1}foo${m2} = 0 }"""
+      )
+
+      val p1 = Project.dependingOn(p0).withSources(
+        code"""object B { val ${m3}bar${m4} = A.${m5}foo${m6} }"""
+      )
+
+      val p2 = Project.dependingOn(p1).withSources(
+        code"""object C { val ${m7}baz${m8} = A.${m9}foo${m10} + B.${m11}bar${m12} }"""
+      )
+
+      withProjects(p0, p1, p2).rename(m, "NewName", expectations)
+    }
+
+    testRename(m1, Set(m1 to m2, m5 to m6, m9 to m10))
+    testRename(m5, Set(m1 to m2, m5 to m6, m9 to m10))
+    testRename(m9, Set(m1 to m2, m5 to m6, m9 to m10))
+
+    testRename(m3, Set(m3 to m4, m11 to m12))
+    testRename(m11, Set(m3 to m4, m11 to m12))
+
+    testRename(m7, Set(m7 to m8))
+  }
+
+  @Test def renameClassMultiProject: Unit = {
+    val m21 = new CodeMarker("m21")
+    val m22 = new CodeMarker("m22")
+    val m23 = new CodeMarker("m23")
+    val m24 = new CodeMarker("m24")
+    val m25 = new CodeMarker("m25")
+    val m26 = new CodeMarker("m26")
+    val m27 = new CodeMarker("m27")
+    val m28 = new CodeMarker("m28")
+    def testRename(m: CodeMarker, expectations: Set[CodeRange]) = {
+      val p0 = Project.withSources(
+        code"""package a
+               object ${m1}A${m2} { class ${m3}B${m4} }"""
+      )
+
+      val p1 = Project.dependingOn(p0).withSources(
+        code"""package b
+               import a.${m5}A${m6}.{${m7}B${m8} => ${m9}AB${m10}}
+               object ${m11}B${m12} { class ${m13}C${m14} extends ${m15}AB${m16} }"""
+      )
+
+      val p2 = Project.dependingOn(p1).withSources(
+        code"""package c
+               import b.${m17}B${m18}.{${m19}C${m20} => ${m21}BC${m22}}
+               object ${m23}C${m24} { class ${m25}D${m26} extends ${m27}BC${m28} }"""
+      )
+
+      withProjects(p0, p1, p2).rename(m, "NewName", expectations)
+    }
+
+    testRename(m1, Set(m1 to m2, m5 to m6))
+    testRename(m5, Set(m1 to m2, m5 to m6))
+
+    testRename(m3, Set(m3 to m4, m7 to m8))
+    testRename(m7, Set(m3 to m4, m7 to m8))
+
+    testRename(m9, Set(m9 to m10, m15 to m16))
+    testRename(m15, Set(m9 to m10, m15 to m16))
 
+    testRename(m11, Set(m11 to m12, m17 to m18))
+    testRename(m17, Set(m11 to m12, m17 to m18))
+
+    testRename(m13, Set(m13 to m14, m19 to m20))
+    testRename(m19, Set(m13 to m14, m19 to m20))
+
+    testRename(m21, Set(m21 to m22, m27 to m28))
+    testRename(m27, Set(m21 to m22, m27 to m28))
+
+    testRename(m23, Set(m23 to m24))
+
+    testRename(m25, Set(m25 to m26))
+
+  }
 
 }