Adds ToolchainConstructor interface and implementations.

ToolchainConstructor is used to create instances of ToolchainInfo, for
toolchain-aware rule sets.

Part of #2219.

Change-Id: Iae4e519b156910cc28704b3ca5b11e57dd561107
PiperOrigin-RevId: 156303854

12 files changed, 212 insertions, 74 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/platform/ToolchainInfo.java b/src/main/java/com/google/devtools/build/lib/analysis/platform/ToolchainInfo.java
index 1e5e45f462..7c7d216ffb 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/platform/ToolchainInfo.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/platform/ToolchainInfo.java
@@ -50,15 +50,18 @@ public class ToolchainInfo extends SkylarkClassObject {
   public static final SkylarkProviderIdentifier SKYLARK_IDENTIFIER =
       SkylarkProviderIdentifier.forKey(SKYLARK_CONSTRUCTOR.getKey());
 
+  private final ClassObjectConstructor.Key toolchainConstructorKey;
   private final ImmutableList<ConstraintValueInfo> execConstraints;
   private final ImmutableList<ConstraintValueInfo> targetConstraints;
 
   public ToolchainInfo(
+      ClassObjectConstructor.Key toolchainConstructorKey,
       Iterable<ConstraintValueInfo> execConstraints,
       Iterable<ConstraintValueInfo> targetConstraints,
       Map<String, Object> toolchainData,
       Location loc) {
     this(
+        toolchainConstructorKey,
         ImmutableList.copyOf(execConstraints),
         ImmutableList.copyOf(targetConstraints),
         toolchainData,
@@ -66,6 +69,7 @@ public class ToolchainInfo extends SkylarkClassObject {
   }
 
   public ToolchainInfo(
+      ClassObjectConstructor.Key toolchainConstructorKey,
       ImmutableList<ConstraintValueInfo> execConstraints,
       ImmutableList<ConstraintValueInfo> targetConstraints,
       Map<String, Object> toolchainData,
@@ -73,16 +77,22 @@ public class ToolchainInfo extends SkylarkClassObject {
     super(
         SKYLARK_CONSTRUCTOR,
         ImmutableMap.<String, Object>builder()
+            .put("toolchain_type", toolchainConstructorKey)
             .put("exec_compatible_with", execConstraints)
             .put("target_compatible_with", targetConstraints)
             .putAll(toolchainData)
             .build(),
         loc);
 
+    this.toolchainConstructorKey = toolchainConstructorKey;
     this.execConstraints = execConstraints;
     this.targetConstraints = targetConstraints;
   }
 
+  public ClassObjectConstructor.Key toolchainConstructorKey() {
+    return toolchainConstructorKey;
+  }
+
   @SkylarkCallable(
     name = "exec_compatible_with",
     doc = "The constraints on the execution platforms this toolchain supports.",
diff --git a/src/main/java/com/google/devtools/build/lib/packages/ClassObjectConstructor.java b/src/main/java/com/google/devtools/build/lib/packages/ClassObjectConstructor.java
index 8275e6a69d..9bce718d38 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/ClassObjectConstructor.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/ClassObjectConstructor.java
@@ -68,7 +68,6 @@ public abstract class ClassObjectConstructor extends BaseFunction {
     super(name, signature, location);
   }
 
-
   /**
    * Has this {@link ClassObjectConstructor} been exported?
    * All native constructors are always exported. Skylark constructors are exported
diff --git a/src/main/java/com/google/devtools/build/lib/packages/SkylarkClassObjectConstructor.java b/src/main/java/com/google/devtools/build/lib/packages/SkylarkClassObjectConstructor.java
index 9a6605de5f..f49d118ce7 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/SkylarkClassObjectConstructor.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/SkylarkClassObjectConstructor.java
@@ -25,13 +25,12 @@ import java.util.Objects;
 import javax.annotation.Nullable;
 
 /**
- *  Declared provider defined in Skylark.
+ * Declared provider defined in Skylark.
  *
- *  This is a result of calling {@code provider()} function from Skylark
- *  ({@link com.google.devtools.build.lib.rules.SkylarkRuleClassFunctions#provider}).
+ * <p>This is a result of calling {@code provider()} function from Skylark ({@link
+ * com.google.devtools.build.lib.rules.SkylarkRuleClassFunctions#provider}).
  */
-public final class SkylarkClassObjectConstructor
-    extends ClassObjectConstructor
+public class SkylarkClassObjectConstructor extends ClassObjectConstructor
     implements SkylarkExportable {
 
   private static final FunctionSignature.WithValues<Object, SkylarkType> SIGNATURE =
diff --git a/src/main/java/com/google/devtools/build/lib/packages/ToolchainConstructor.java b/src/main/java/com/google/devtools/build/lib/packages/ToolchainConstructor.java
new file mode 100644
index 0000000000..fe21f43ed0
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/packages/ToolchainConstructor.java
@@ -0,0 +1,26 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.packages;
+
+import com.google.devtools.build.lib.packages.ClassObjectConstructor.Key;
+
+/**
+ * Constructor that can be used to generate toolchains. The key returned by {@link #getKey()} is a
+ * serializable representation of the constructor and serves to identify toolchains of the same
+ * type.
+ */
+public interface ToolchainConstructor {
+
+  Key getKey();
+}
diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/NativeToolchainConstructor.java b/src/main/java/com/google/devtools/build/lib/rules/platform/NativeToolchainConstructor.java
new file mode 100644
index 0000000000..6d62b25a48
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/NativeToolchainConstructor.java
@@ -0,0 +1,37 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.rules.platform;
+
+import com.google.devtools.build.lib.packages.NativeClassObjectConstructor;
+import com.google.devtools.build.lib.packages.ToolchainConstructor;
+import com.google.devtools.build.lib.syntax.Environment;
+import com.google.devtools.build.lib.syntax.EvalException;
+import com.google.devtools.build.lib.syntax.FuncallExpression;
+import javax.annotation.Nullable;
+
+/** Native value that can be used to create toolchains. */
+public class NativeToolchainConstructor extends NativeClassObjectConstructor
+    implements ToolchainConstructor {
+
+  protected NativeToolchainConstructor(String name) {
+    super(name);
+  }
+
+  // TODO(katre): Implement this.
+  @Override
+  protected Object call(Object[] args, @Nullable FuncallExpression ast, @Nullable Environment env)
+      throws EvalException, InterruptedException {
+    throw new IllegalStateException("Native toolchains not yet implemented.");
+  }
+}
diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java b/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
index 09d31c15e5..5a4a25924c 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/PlatformCommon.java
@@ -14,24 +14,20 @@
 
 package com.google.devtools.build.lib.rules.platform;
 
-import com.google.common.collect.ImmutableMap;
-import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.analysis.platform.ConstraintSettingInfo;
 import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo;
 import com.google.devtools.build.lib.analysis.platform.PlatformInfo;
 import com.google.devtools.build.lib.analysis.platform.ToolchainInfo;
 import com.google.devtools.build.lib.events.Location;
 import com.google.devtools.build.lib.packages.ClassObjectConstructor;
+import com.google.devtools.build.lib.packages.ToolchainConstructor;
 import com.google.devtools.build.lib.skylarkinterface.Param;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkCallable;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkModule;
 import com.google.devtools.build.lib.skylarkinterface.SkylarkSignature;
 import com.google.devtools.build.lib.syntax.BuiltinFunction;
 import com.google.devtools.build.lib.syntax.EvalException;
-import com.google.devtools.build.lib.syntax.SkylarkDict;
-import com.google.devtools.build.lib.syntax.SkylarkList;
 import com.google.devtools.build.lib.syntax.SkylarkSignatureProcessor;
-import com.google.devtools.build.lib.syntax.Type.ConversionException;
 
 /** Skylark namespace used to interact with Blaze's platform APIs. */
 @SkylarkModule(
@@ -77,62 +73,22 @@ public class PlatformCommon {
   }
 
   @SkylarkSignature(
-    name = "toolchain",
-    doc =
-        "<i>(Experimental)</i> "
-            + "Returns a toolchain provider that can be configured to provide rule implementations "
-            + "access to needed configuration.",
+    name = "toolchain_type",
+    doc = "",
+    documented = false,
     objectType = PlatformCommon.class,
-    returnType = ToolchainInfo.class,
+    returnType = ToolchainConstructor.class,
     parameters = {
       @Param(name = "self", type = PlatformCommon.class, doc = "the platform_rules instance"),
-      @Param(
-        name = "exec_compatible_with",
-        type = SkylarkList.class,
-        generic1 = TransitiveInfoCollection.class,
-        defaultValue = "[]",
-        named = true,
-        positional = false,
-        doc = "Constraints the platform must fulfill to execute this toolchain."
-      ),
-      @Param(
-        name = "target_compatible_with",
-        type = SkylarkList.class,
-        generic1 = TransitiveInfoCollection.class,
-        defaultValue = "[]",
-        named = true,
-        positional = false,
-        doc = "Constraints fulfilled by the target platform for this toolchain."
-      ),
     },
-    extraKeywords =
-        @Param(
-          name = "toolchainData",
-          doc = "Extra information stored for the consumer of the toolchain."
-        ),
     useLocation = true
   )
-  private static final BuiltinFunction createToolchain =
-      new BuiltinFunction("toolchain") {
+  private static final BuiltinFunction createToolchainType =
+      new BuiltinFunction("toolchain_type") {
         @SuppressWarnings("unchecked")
-        public ToolchainInfo invoke(
-            PlatformCommon self,
-            SkylarkList<TransitiveInfoCollection> execCompatibleWith,
-            SkylarkList<TransitiveInfoCollection> targetCompatibleWith,
-            SkylarkDict<String, Object> skylarkToolchainData,
-            Location loc)
-            throws ConversionException, EvalException {
-
-          Iterable<ConstraintValueInfo> execConstraints =
-              ConstraintValue.constraintValues(execCompatibleWith);
-          Iterable<ConstraintValueInfo> targetConstraints =
-              ConstraintValue.constraintValues(targetCompatibleWith);
-          ImmutableMap<String, Object> toolchainData =
-              ImmutableMap.copyOf(
-                  SkylarkDict.castSkylarkDictOrNoneToDict(
-                      skylarkToolchainData, String.class, Object.class, "toolchainData"));
-
-          return new ToolchainInfo(execConstraints, targetConstraints, toolchainData, loc);
+        public ToolchainConstructor invoke(PlatformCommon self, Location loc)
+            throws EvalException {
+          return new SkylarkToolchainConstructor(loc);
         }
       };
 
diff --git a/src/main/java/com/google/devtools/build/lib/rules/platform/SkylarkToolchainConstructor.java b/src/main/java/com/google/devtools/build/lib/rules/platform/SkylarkToolchainConstructor.java
new file mode 100644
index 0000000000..73063493eb
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/platform/SkylarkToolchainConstructor.java
@@ -0,0 +1,84 @@
+// Copyright 2017 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+package com.google.devtools.build.lib.rules.platform;
+
+import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.ImmutableSet;
+import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
+import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo;
+import com.google.devtools.build.lib.analysis.platform.ToolchainInfo;
+import com.google.devtools.build.lib.events.Location;
+import com.google.devtools.build.lib.packages.SkylarkClassObjectConstructor;
+import com.google.devtools.build.lib.packages.ToolchainConstructor;
+import com.google.devtools.build.lib.syntax.Environment;
+import com.google.devtools.build.lib.syntax.EvalException;
+import com.google.devtools.build.lib.syntax.FuncallExpression;
+import com.google.devtools.build.lib.syntax.SkylarkDict;
+import com.google.devtools.build.lib.syntax.SkylarkList;
+import java.util.Map;
+import java.util.Set;
+import javax.annotation.Nullable;
+
+/** Skylark value that can be used to create toolchains. */
+public class SkylarkToolchainConstructor extends SkylarkClassObjectConstructor
+    implements ToolchainConstructor {
+
+  private static final String EXEC_COMPATIBLE_WITH = "exec_compatible_with";
+  private static final String TARGET_COMPATIBLE_WITH = "target_compatible_with";
+
+  public SkylarkToolchainConstructor(Location location) {
+    super(
+        "<no name>", // name is set on export.
+        location);
+  }
+
+  @Override
+  @Nullable
+  protected Object call(Object[] args, @Nullable FuncallExpression ast, @Nullable Environment env)
+      throws EvalException, InterruptedException {
+
+    // Decode arguments.
+    @SuppressWarnings("unchecked")
+    SkylarkDict<String, Object> receivedArguments = (SkylarkDict<String, Object>) args[0];
+    @SuppressWarnings("unchecked")
+    Iterable<ConstraintValueInfo> execConstraints =
+        ConstraintValue.constraintValues(
+            (SkylarkList<TransitiveInfoCollection>) receivedArguments.get(EXEC_COMPATIBLE_WITH));
+    @SuppressWarnings("unchecked")
+    Iterable<ConstraintValueInfo> targetConstraints =
+        ConstraintValue.constraintValues(
+            (SkylarkList<TransitiveInfoCollection>) receivedArguments.get(TARGET_COMPATIBLE_WITH));
+    Map<String, Object> toolchainData =
+        collectData(
+            receivedArguments, ImmutableSet.of(EXEC_COMPATIBLE_WITH, TARGET_COMPATIBLE_WITH));
+    Location loc = ast != null ? ast.getLocation() : Location.BUILTIN;
+
+    return new ToolchainInfo(getKey(), execConstraints, targetConstraints, toolchainData, loc);
+  }
+
+  private Map<String, Object> collectData(
+      SkylarkDict<String, Object> receivedArguments, Set<String> ignoredKeys) {
+
+    ImmutableMap.Builder<String, Object> builder = new ImmutableMap.Builder<>();
+    for (Map.Entry<String, Object> entry : receivedArguments.entrySet()) {
+      String key = entry.getKey();
+      Object value = entry.getValue();
+      if (!ignoredKeys.contains(key)) {
+        builder.put(key, value);
+      }
+    }
+
+    return builder.build();
+  }
+}
diff --git a/src/test/java/com/google/devtools/build/lib/analysis/platform/BUILD b/src/test/java/com/google/devtools/build/lib/analysis/platform/BUILD
index 5993fc5516..1e752eeab8 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/platform/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/analysis/platform/BUILD
@@ -11,6 +11,7 @@ java_test(
     deps = [
         "//src/main/java/com/google/devtools/build/lib:events",
         "//src/main/java/com/google/devtools/build/lib:os_util",
+        "//src/main/java/com/google/devtools/build/lib:packages-internal",
         "//src/main/java/com/google/devtools/build/lib:syntax",
         "//src/main/java/com/google/devtools/build/lib:util",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
diff --git a/src/test/java/com/google/devtools/build/lib/analysis/platform/PlatformProvidersTest.java b/src/test/java/com/google/devtools/build/lib/analysis/platform/PlatformProvidersTest.java
index 235532c2d8..35f60cd662 100644
--- a/src/test/java/com/google/devtools/build/lib/analysis/platform/PlatformProvidersTest.java
+++ b/src/test/java/com/google/devtools/build/lib/analysis/platform/PlatformProvidersTest.java
@@ -19,6 +19,7 @@ import com.google.common.collect.ImmutableMap;
 import com.google.common.testing.EqualsTester;
 import com.google.devtools.build.lib.analysis.util.BuildViewTestCase;
 import com.google.devtools.build.lib.events.Location;
+import com.google.devtools.build.lib.packages.ClassObjectConstructor;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
@@ -108,6 +109,7 @@ public class PlatformProvidersTest extends BuildViewTestCase {
 
   @Test
   public void toolchainInfo_equalsTester() throws Exception {
+    ClassObjectConstructor.Key key = new ClassObjectConstructor.Key() {};
     ConstraintSettingInfo setting1 = ConstraintSettingInfo.create(makeLabel("//constraint:basic"));
     ConstraintSettingInfo setting2 = ConstraintSettingInfo.create(makeLabel("//constraint:other"));
 
@@ -122,11 +124,21 @@ public class PlatformProvidersTest extends BuildViewTestCase {
         .addEqualityGroup(
             // Base case.
             new ToolchainInfo(
+                key,
                 ImmutableList.of(value1, value2),
                 ImmutableList.of(value1, value3),
                 ImmutableMap.<String, Object>of("foo", "val1", "bar", "val2"),
                 Location.BUILTIN),
             new ToolchainInfo(
+                key,
+                ImmutableList.of(value1, value2),
+                ImmutableList.of(value1, value3),
+                ImmutableMap.<String, Object>of("foo", "val1", "bar", "val2"),
+                Location.BUILTIN))
+        .addEqualityGroup(
+            // Different type.
+            new ToolchainInfo(
+                new ClassObjectConstructor.Key() {},
                 ImmutableList.of(value1, value2),
                 ImmutableList.of(value1, value3),
                 ImmutableMap.<String, Object>of("foo", "val1", "bar", "val2"),
@@ -134,6 +146,7 @@ public class PlatformProvidersTest extends BuildViewTestCase {
         .addEqualityGroup(
             // Different target constraints.
             new ToolchainInfo(
+                key,
                 ImmutableList.of(value1, value2),
                 ImmutableList.of(value1, value2),
                 ImmutableMap.<String, Object>of("foo", "val1", "bar", "val2"),
@@ -141,6 +154,7 @@ public class PlatformProvidersTest extends BuildViewTestCase {
         .addEqualityGroup(
             // Different data.
             new ToolchainInfo(
+                key,
                 ImmutableList.of(value1, value2),
                 ImmutableList.of(value1, value3),
                 ImmutableMap.<String, Object>of("foo", "val1", "bar", "val3"),
diff --git a/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD b/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
index daf896eea9..981b5b15f2 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
+++ b/src/test/java/com/google/devtools/build/lib/rules/platform/BUILD
@@ -11,6 +11,7 @@ java_test(
     deps = [
         "//src/main/java/com/google/devtools/build/lib:build-base",
         "//src/main/java/com/google/devtools/build/lib:os_util",
+        "//src/main/java/com/google/devtools/build/lib:packages-internal",
         "//src/main/java/com/google/devtools/build/lib:syntax",
         "//src/main/java/com/google/devtools/build/lib:util",
         "//src/main/java/com/google/devtools/build/lib/analysis/platform",
diff --git a/src/test/java/com/google/devtools/build/lib/rules/platform/PlatformCommonTest.java b/src/test/java/com/google/devtools/build/lib/rules/platform/PlatformCommonTest.java
index f3cd8255b1..dc04069f97 100644
--- a/src/test/java/com/google/devtools/build/lib/rules/platform/PlatformCommonTest.java
+++ b/src/test/java/com/google/devtools/build/lib/rules/platform/PlatformCommonTest.java
@@ -17,11 +17,11 @@ package com.google.devtools.build.lib.rules.platform;
 import static com.google.common.truth.Truth.assertThat;
 
 import com.google.devtools.build.lib.analysis.ConfiguredTarget;
-import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.analysis.platform.ConstraintSettingInfo;
 import com.google.devtools.build.lib.analysis.platform.ConstraintValueInfo;
+import com.google.devtools.build.lib.analysis.platform.ToolchainInfo;
+import com.google.devtools.build.lib.packages.SkylarkClassObjectConstructor;
 import com.google.devtools.build.lib.skylark.util.SkylarkTestCase;
-import java.util.List;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
@@ -31,20 +31,21 @@ import org.junit.runners.JUnit4;
 public class PlatformCommonTest extends SkylarkTestCase {
 
   @Test
-  public void testCreateToolchain() throws Exception {
+  public void testCreateToolchainType() throws Exception {
     scratch.file(
-        "test/toolchain.bzl",
+        "test/toolchain_type.bzl",
+        "test_toolchain_type = platform_common.toolchain_type()",
         "def _impl(ctx):",
-        "    return platform_common.toolchain(",
+        "    toolchain = test_toolchain_type(",
         "        exec_compatible_with = ctx.attr.exec_compatible_with,",
         "        target_compatible_with = ctx.attr.target_compatible_with,",
         "        extra_label = ctx.attr.extra_label,",
         "        extra_str = ctx.attr.extra_str,",
         "    )",
+        "    return [toolchain]",
         "test_toolchain = rule(",
         "    implementation = _impl,",
         "    attrs = {",
-        "       'runs': attr.label_list(allow_files=True),",
         "       'exec_compatible_with': attr.label_list(",
         "           providers = [platform_common.ConstraintValueInfo]),",
         "       'target_compatible_with': attr.label_list(",
@@ -55,7 +56,7 @@ public class PlatformCommonTest extends SkylarkTestCase {
         ")");
     scratch.file(
         "test/BUILD",
-        "load(':toolchain.bzl', 'test_toolchain')",
+        "load(':toolchain_type.bzl', 'test_toolchain')",
         "constraint_setting(name = 'os')",
         "constraint_value(name = 'linux',",
         "    constraint_setting = ':os')",
@@ -73,20 +74,29 @@ public class PlatformCommonTest extends SkylarkTestCase {
         "    extra_label = ':dep_rule',",
         "    extra_str = 'bar',",
         ")");
-    TransitiveInfoCollection toolchainProvider = getConfiguredTarget("//test:linux_toolchain");
-    assertThat(toolchainProvider).isNotNull();
 
-    assertThat((List<?>) toolchainProvider.get("exec_compatible_with"))
+    ConfiguredTarget configuredTarget = getConfiguredTarget("//test:linux_toolchain");
+    ToolchainInfo toolchainInfo =
+        (ToolchainInfo) configuredTarget.get(ToolchainInfo.SKYLARK_IDENTIFIER);
+    assertThat(toolchainInfo).isNotNull();
+
+    assertThat(toolchainInfo.toolchainConstructorKey()).isNotNull();
+    assertThat(toolchainInfo.toolchainConstructorKey())
+        .isEqualTo(
+            new SkylarkClassObjectConstructor.SkylarkKey(
+                makeLabel("//test:toolchain_type.bzl"), "test_toolchain_type"));
+
+    assertThat(toolchainInfo.execConstraints())
         .containsExactly(
             ConstraintValueInfo.create(
                 ConstraintSettingInfo.create(makeLabel("//test:os")), makeLabel("//test:linux")));
-    assertThat((List<?>) toolchainProvider.get("target_compatible_with"))
+    assertThat(toolchainInfo.targetConstraints())
         .containsExactly(
             ConstraintValueInfo.create(
                 ConstraintSettingInfo.create(makeLabel("//test:os")), makeLabel("//test:mac")));
 
-    assertThat(((ConfiguredTarget) toolchainProvider.get("extra_label")).getLabel())
+    assertThat(((ConfiguredTarget) toolchainInfo.getValue("extra_label")).getLabel())
         .isEqualTo(makeLabel("//test:dep_rule"));
-    assertThat(toolchainProvider.get("extra_str")).isEqualTo("bar");
+    assertThat(toolchainInfo.getValue("extra_str")).isEqualTo("bar");
   }
 }
diff --git a/src/test/shell/bazel/toolchain_test.sh b/src/test/shell/bazel/toolchain_test.sh
index 389c12ba23..51c3482aef 100755
--- a/src/test/shell/bazel/toolchain_test.sh
+++ b/src/test/shell/bazel/toolchain_test.sh
@@ -62,8 +62,9 @@ function test_toolchain_rule() {
 
   mkdir -p toolchain
   cat >> toolchain/toolchain.bzl <<EOF
+test_toolchain_type = platform_common.toolchain_type()
 def _test_toolchain_impl(ctx):
-  toolchain = platform_common.toolchain(
+  toolchain = test_toolchain_type(
       exec_compatible_with = ctx.attr.exec_compatible_with,
       target_compatible_with = ctx.attr.target_compatible_with,
       extra_label = ctx.attr.extra_label,