| // Copyright 2021 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.bazel.bzlmod; |
| |
| import com.google.auto.value.AutoValue; |
| import com.google.common.base.Preconditions; |
| import com.google.common.base.Splitter; |
| import com.google.common.collect.ImmutableMap; |
| import com.google.devtools.build.lib.cmdline.RepositoryName; |
| import java.util.Comparator; |
| import java.util.List; |
| |
| /** A module name, version pair that identifies a module in the external dependency graph. */ |
| @AutoValue |
| public abstract class ModuleKey { |
| |
| /** |
| * A mapping from module name to repository name for certain special "well-known" modules. |
| * |
| * <p>The repository name of certain modules are required to be exact strings (instead of the |
| * normal format seen in {@link #getCanonicalRepoName(boolean)}) due to backwards compatibility |
| * reasons. For example, bazel_tools must be known as "@bazel_tools" for WORKSPACE repos to work |
| * correctly. |
| */ |
| // Keep in sync with src/tools/bzlmod/utils.bzl. |
| private static final ImmutableMap<String, RepositoryName> WELL_KNOWN_MODULES = |
| ImmutableMap.of( |
| "bazel_tools", |
| RepositoryName.BAZEL_TOOLS, |
| "local_config_platform", |
| RepositoryName.createUnvalidated("local_config_platform"), |
| // Ensures that references to "@platforms" in WORKSPACE files resolve to the repository of |
| // the "platforms" module. Without this, constraints on toolchains registered in WORKSPACE |
| // would reference the "platforms" repository defined in the WORKSPACE suffix, whereas |
| // the host constraints generated by local_config_platform would reference the "platforms" |
| // module repository, resulting in a toolchain resolution mismatch. |
| "platforms", |
| RepositoryName.createUnvalidated("platforms")); |
| |
| public static final ModuleKey ROOT = create("", Version.EMPTY); |
| |
| public static final Comparator<ModuleKey> LEXICOGRAPHIC_COMPARATOR = |
| Comparator.comparing(ModuleKey::getName).thenComparing(ModuleKey::getVersion); |
| |
| public static ModuleKey create(String name, Version version) { |
| return new AutoValue_ModuleKey(name, version); |
| } |
| |
| /** The name of the module. Must be empty for the root module. */ |
| public abstract String getName(); |
| |
| /** The version of the module. Must be empty iff the module has a {@link NonRegistryOverride}. */ |
| public abstract Version getVersion(); |
| |
| @Override |
| public final String toString() { |
| if (this.equals(ROOT)) { |
| return "<root>"; |
| } |
| return getName() + "@" + (getVersion().isEmpty() ? "_" : getVersion().toString()); |
| } |
| |
| /** |
| * Returns the canonical name of the repo backing this module, including its version. This name is |
| * always guaranteed to be unique. |
| * |
| * <p>This method must not be called if the module has a {@link NonRegistryOverride}. |
| */ |
| public RepositoryName getCanonicalRepoNameWithVersion() { |
| return getCanonicalRepoName(/* includeVersion= */ true); |
| } |
| |
| /** |
| * Returns the canonical name of the repo backing this module, excluding its version. This name is |
| * only guaranteed to be unique when there is a single version of the module in the entire dep |
| * graph. |
| */ |
| public RepositoryName getCanonicalRepoNameWithoutVersion() { |
| return getCanonicalRepoName(/* includeVersion= */ false); |
| } |
| |
| private RepositoryName getCanonicalRepoName(boolean includeVersion) { |
| if (WELL_KNOWN_MODULES.containsKey(getName())) { |
| return WELL_KNOWN_MODULES.get(getName()); |
| } |
| if (ROOT.equals(this)) { |
| return RepositoryName.MAIN; |
| } |
| String suffix; |
| if (includeVersion) { |
| // getVersion().isEmpty() is true only for modules with non-registry overrides, which enforce |
| // that there is a single version of the module in the dep graph. |
| Preconditions.checkState(!getVersion().isEmpty()); |
| suffix = getVersion().toString(); |
| } else { |
| // This results in canonical repository names such as `rules_foo~` for the module `rules_foo`. |
| // This particular format is chosen since: |
| // * The tilde ensures that canonical and apparent repository names can be distinguished even |
| // in contexts where users don't rely on `@` vs. `@@` to distinguish between them. For |
| // example, this means that the repo mapping as applied by runfiles libraries is idempotent. |
| // * Appending a tilde even in the case of a unique version means that module repository |
| // names always contain the same number of tilde-separated components, which improves |
| // compatibility with existing logic based on the `rules_foo~1.2.3` format. |
| // * By making it so that the module name and the canonical repository name of a module are |
| // never identical, even when using an override, we introduce "grease" that intentionally |
| // tickles bugs in code that doesn't properly distinguish between the two, e.g., by not |
| // applying repo mappings. Otherwise, these bugs could go unnoticed in BCR test modules and |
| // would only be discovered when used with a `multiple_version_override`, which is very |
| // rarely used. |
| suffix = ""; |
| } |
| return RepositoryName.createUnvalidated(String.format("%s~%s", getName(), suffix)); |
| } |
| |
| public static ModuleKey fromString(String s) throws Version.ParseException { |
| if (s.equals("<root>")) { |
| return ModuleKey.ROOT; |
| } |
| List<String> parts = Splitter.on('@').splitToList(s); |
| if (parts.get(1).equals("_")) { |
| return ModuleKey.create(parts.get(0), Version.EMPTY); |
| } |
| |
| Version version = Version.parse(parts.get(1)); |
| return ModuleKey.create(parts.get(0), version); |
| } |
| } |