Fix Meta.enso_project (#10192)

Fixes `Standard.Base.Meta.Enso_Project.enso_project` to return a project descriptor for the *main* project, i.e., the one configured as a *root* for the engine.

# Important Notes
`enso_project` builtin no longer iterates the stack frames to infer the project descriptor. It derives it from the default package repository.

distribution/lib/Standard/Base/0.0.0-dev/src/Meta/Enso_Project.enso

@@ -45,7 +45,7 @@ type Project_Description
        Arguments:
        - prim_root_file: The primitive root file of the project.
        - prim_config: The primitive config of the project.
-    Value prim_root_file prim_config
+    private Value prim_root_file prim_config
 
     ## GROUP Metadata
        ICON folder

distribution/lib/Standard/Examples/0.0.0-dev/src/Main.enso

@@ -17,13 +17,15 @@ type Example_Error_Type
        - message: The message contained in the error type.
     Error message
 
-## The standard library data directory.
+## The data directory of the Examples project.
 data_dir : File
-data_dir = enso_project.data
+data_dir = 
+    this_proj = Project_Description.new Standard.Examples.Main
+    this_proj.data
 
 ## An example CSV file for experimenting with Table and its APIs.
 csv : File
-csv = enso_project.data / "food_shop_inventory.csv"
+csv = data_dir / "food_shop_inventory.csv"
 
 ## The path to the CSV.
 csv_path : Text
@@ -39,7 +41,7 @@ csv_path = csv.path
 xls : File
 xls =
     url = "https://enso-data-samples.s3.us-west-1.amazonaws.com/spreadsheet.xls"
-    file = enso_project.data / 'spreadsheet.xls'
+    file = data_dir / 'spreadsheet.xls'
     if file.exists.not then
         Context.Output.with_enabled <| HTTP.fetch url . body . write file
     file
@@ -54,15 +56,15 @@ xls =
 xlsx : File
 xlsx =
     url = "https://enso-data-samples.s3.us-west-1.amazonaws.com/spreadsheet.xlsx"
-    file = enso_project.data / 'spreadsheet.xlsx'
+    file = data_dir / 'spreadsheet.xlsx'
     if file.exists.not then
         Context.Output.with_enabled <| HTTP.fetch url . body . write file
     file
 
 ## A file that is used for writing temporary data as part of tests.
 scratch_file : File
 scratch_file =
-    file = enso_project.data / "scratch_file"
+    file = data_dir / "scratch_file"
     if file.exists.not then Nothing else
         Context.Output.with_enabled <| file.delete
     file
@@ -169,7 +171,7 @@ uri = URI.parse "http://user:[email protected]/foo/bar?key=val"
 image_file : File
 image_file =
     url = "https://upload.wikimedia.org/wikipedia/commons/thumb/e/e9/Hue_alpha_falloff.png/320px-Hue_alpha_falloff.png"
-    file = enso_project.data / "image.png"
+    file = data_dir / "image.png"
     if file.exists.not then
         Context.Output.with_enabled <| HTTP.fetch url . body . write file
     file
@@ -258,12 +260,12 @@ inventory_table = csv.read
 ## A simple table that contains basic item popularity data for the food shop.
 popularity_table : Table
 popularity_table =
-    (enso_project.data / "food_shop_popularity.csv") . read
+    (data_dir / "food_shop_popularity.csv") . read
 
 ## A simple tablethat contains basic transaction data for the food shop.
 transactions_table : Table
 transactions_table =
-    (enso_project.data / "food_shop_transactions.csv") . read
+    (data_dir / "food_shop_transactions.csv") . read
 
 ## An example regex match.
 match : Match

engine/runtime-integration-tests/src/test/java/org/enso/interpreter/test/meta/EnsoProjectTest.java

@@ -0,0 +1,125 @@
+package org.enso.interpreter.test.meta;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.notNullValue;
+
+import java.io.IOException;
+import java.util.List;
+import java.util.Set;
+import org.enso.common.LanguageInfo;
+import org.enso.interpreter.util.ScalaConversions;
+import org.enso.pkg.QualifiedName;
+import org.enso.polyglot.PolyglotContext;
+import org.enso.polyglot.RuntimeOptions;
+import org.enso.test.utils.ContextUtils;
+import org.enso.test.utils.ProjectUtils;
+import org.enso.test.utils.SourceModule;
+import org.graalvm.polyglot.Source;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+public class EnsoProjectTest {
+  @Rule public TemporaryFolder temporaryFolder = new TemporaryFolder();
+
+  @Test
+  public void noProjectWhenEvaluatingSingleFile() {
+    try (var ctx = ContextUtils.createDefaultContext()) {
+      var res =
+          ContextUtils.evalModule(
+              ctx,
+              """
+          from Standard.Base import all
+          from Standard.Base.Errors.Common import Module_Not_In_Package_Error
+
+          main =
+              enso_project.is_error
+          """);
+      assertThat(res, notNullValue());
+      assertThat(res.asBoolean(), is(true));
+    }
+  }
+
+  @Test
+  public void ensoProjectWorksInOneProject() throws IOException {
+    var mainMod =
+        new SourceModule(
+            QualifiedName.fromString("Main"),
+            """
+        from Standard.Base import all
+        main =
+            enso_project.name
+        """);
+    var projDir = temporaryFolder.newFolder().toPath();
+    ProjectUtils.createProject("Proj", Set.of(mainMod), projDir);
+    ProjectUtils.testProjectRun(
+        projDir,
+        (res) -> {
+          assertThat(res.asString(), is("Proj"));
+        });
+  }
+
+  @Test
+  public void ensoProjectWorksInTwoProjects() throws IOException {
+    var mainMod1 =
+        new SourceModule(
+            QualifiedName.fromString("Main"),
+            """
+        from Standard.Base import all
+
+        get_enso_project_name =
+            enso_project.name
+        """);
+    var mainMod2 =
+        new SourceModule(
+            QualifiedName.fromString("Main"),
+            """
+        from local.Proj1 import get_enso_project_name
+        main =
+            get_enso_project_name
+        """);
+    var projDir1 = temporaryFolder.newFolder().toPath();
+    var projDir2 = temporaryFolder.newFolder().toPath();
+    ProjectUtils.createProject("Proj1", Set.of(mainMod1), projDir1);
+    ProjectUtils.createProject("Proj2", Set.of(mainMod2), projDir2);
+    ProjectUtils.testProjectRun(
+        projDir2,
+        (res) -> {
+          assertThat(res.asString(), is("Proj2"));
+        });
+  }
+
+  @Test
+  public void ensoProjectCanBeCalledFromJava() throws IOException {
+    var mainMod =
+        new SourceModule(
+            QualifiedName.fromString("Main"),
+            """
+        from Standard.Base import all
+        main =
+            42
+        """);
+    var projDir = temporaryFolder.newFolder().toPath();
+    ProjectUtils.createProject("Proj", Set.of(mainMod), projDir);
+    var mainModFile = projDir.resolve("src").resolve("Main.enso");
+    assertThat(mainModFile.toFile().exists(), is(true));
+    try (var ctx =
+        ContextUtils.defaultContextBuilder()
+            .option(RuntimeOptions.PROJECT_ROOT, projDir.toAbsolutePath().toString())
+            .build()) {
+      var mainSrc = Source.newBuilder(LanguageInfo.ID, mainModFile.toFile()).build();
+      // First eval the source so that everything is compiled.
+      ctx.eval(mainSrc);
+      var polyCtx = new PolyglotContext(ctx);
+      var mod = polyCtx.getTopScope().getModule("Standard.Base.Meta.Enso_Project");
+      var assocType = mod.getAssociatedType();
+      var ensoProjMethod = mod.getMethod(assocType, "enso_project").get();
+      var projDescr = ensoProjMethod.execute(ScalaConversions.seq(List.of(assocType)));
+      assertThat(projDescr.hasMembers(), is(true));
+      assertThat(projDescr.getMetaObject().getMetaSimpleName(), is("Project_Description"));
+      assertThat(projDescr.hasMember("name"), is(true));
+      assertThat(projDescr.invokeMember("name").asString(), is("Proj"));
+    }
+  }
+}

engine/runtime/src/main/java/org/enso/interpreter/node/expression/builtin/meta/EnsoProjectNode.java

@@ -3,16 +3,12 @@
 import com.oracle.truffle.api.CompilerDirectives;
 import com.oracle.truffle.api.CompilerDirectives.CompilationFinal;
 import com.oracle.truffle.api.CompilerDirectives.TruffleBoundary;
-import com.oracle.truffle.api.Truffle;
 import com.oracle.truffle.api.TruffleFile;
 import com.oracle.truffle.api.dsl.Specialization;
 import com.oracle.truffle.api.library.CachedLibrary;
 import com.oracle.truffle.api.nodes.Node;
 import java.lang.ref.WeakReference;
-import java.util.Objects;
-import java.util.Optional;
 import org.enso.interpreter.dsl.BuiltinMethod;
-import org.enso.interpreter.node.EnsoRootNode;
 import org.enso.interpreter.runtime.EnsoContext;
 import org.enso.interpreter.runtime.data.EnsoFile;
 import org.enso.interpreter.runtime.data.Type;
@@ -25,7 +21,8 @@
 @BuiltinMethod(
     type = "Project_Description",
     name = "enso_project_builtin",
-    description = "Returns the project description of the project given as the argument")
+    description =
+        "Returns the project description of the project given as the argument, or the main project")
 public abstract class EnsoProjectNode extends Node {
 
   public static EnsoProjectNode build() {
@@ -35,6 +32,10 @@ public static EnsoProjectNode build() {
   /** A weak reference to the context in which this node was last executed. */
   @CompilationFinal private WeakReference<EnsoContext> previousCtxRef = new WeakReference<>(null);
 
+  /**
+   * The project descriptor is cached, as it is safe to assume that it will not change during the
+   * runtime.
+   */
   private Object cachedProjectDescr;
 
   /**
@@ -43,9 +44,8 @@ public static EnsoProjectNode build() {
   public abstract Object execute(Object module);
 
   /**
-   * Fetches the second stack frame from Truffle runtime (note that the first stack frame is the
-   * call of {@code enso_project}) - the caller of {@code enso_project}, and finds in which package
-   * the caller is located.
+   * Returns the project description of the main project, i.e., the project specified as the root to
+   * the engine.
    *
    * @param nothing Nothing, or interop null.
    */
@@ -56,50 +56,14 @@ public Object getCurrentProjectDescr(Object nothing) {
     if (previousCtx == null || cachedProjectDescr == null || previousCtx != ctx) {
       CompilerDirectives.transferToInterpreter();
       previousCtxRef = new WeakReference<>(ctx);
-      // Find the caller of `enso_project`, i.e., of this node, and find in which package
-      // it is located. The first frame is skipped, because it is always
-      // `Enso_Project.enso_project`,
-      // i.e., the first frame is always call of this specialization.
-      Optional<Package<TruffleFile>> pkgOpt =
-          Truffle.getRuntime()
-              .iterateFrames(
-                  frame -> {
-                    var callNode = frame.getCallNode();
-                    assert callNode != null
-                        : "Should skip the first frame, therefore, callNode should not be null";
-                    var callRootNode = callNode.getRootNode();
-                    assert callRootNode != null
-                        : "Should be called only from Enso code, and thus, should always have a"
-                            + " root node";
-                    if (callRootNode instanceof EnsoRootNode ensoRootNode) {
-                      var pkg = ensoRootNode.getModuleScope().getModule().getPackage();
-                      // Don't return null, as that would signal to Truffle that we want to
-                      // continue the iteration.
-                      if (pkg != null) {
-                        return Optional.of(pkg);
-                      } else {
-                        return Optional.empty();
-                      }
-                    } else {
-                      CompilerDirectives.transferToInterpreter();
-                      throw EnsoContext.get(this)
-                          .raiseAssertionPanic(
-                              this,
-                              "Should not reach here: callRootNode = "
-                                  + callRootNode
-                                  + ". Probably not called from Enso?",
-                              null);
-                    }
-                  },
-                  // The first frame is always Enso_Project.enso_project
-                  1);
-      if (pkgOpt.isPresent()) {
-        cachedProjectDescr = createProjectDescriptionAtom(ctx, pkgOpt.get());
+      var mainPkg = getMainProjectFromCtx(ctx);
+      if (mainPkg != null) {
+        cachedProjectDescr = createProjectDescriptionAtom(ctx, mainPkg);
       } else {
         cachedProjectDescr = notInModuleError(ctx);
       }
     }
-    Objects.requireNonNull(cachedProjectDescr);
+    assert cachedProjectDescr != null;
     return cachedProjectDescr;
   }
 
@@ -124,6 +88,14 @@ public Object getOtherProjectDescr(
     }
   }
 
+  private static Package<TruffleFile> getMainProjectFromCtx(EnsoContext ctx) {
+    var mainPkgOpt = ctx.getPackageRepository().getMainProjectPackage();
+    if (mainPkgOpt.isDefined()) {
+      return mainPkgOpt.get();
+    }
+    return null;
+  }
+
   private static Atom createProjectDescriptionAtom(EnsoContext ctx, Package<TruffleFile> pkg) {
     var rootPath = new EnsoFile(pkg.root().normalize());
     var cfg = ctx.asGuestValue(pkg.getConfig());