fix(publish): work around yarn "link:" intransigency

refs npm/npm#15900, refs yarnpkg/yarn#4212

commands/__fixtures__/yarn-link-spec/.yarnrc

@@ -0,0 +1 @@
+workspaces-experimental true

commands/__fixtures__/yarn-link-spec/lerna.json

@@ -0,0 +1,5 @@
+{
+  "version": "1.0.0",
+  "npmClient": "yarn",
+  "useWorkspaces": true
+}

commands/__fixtures__/yarn-link-spec/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "yarn-link-spec",
+  "private": true,
+  "workspaces": [
+    "workspaces/*"
+  ]
+}

commands/__fixtures__/yarn-link-spec/workspaces/package-1/package.json

@@ -0,0 +1,4 @@
+{
+  "name": "package-1",
+  "version": "1.0.0"
+}

commands/__fixtures__/yarn-link-spec/workspaces/package-2/package.json

@@ -0,0 +1,7 @@
+{
+  "name": "package-2",
+  "version": "1.0.0",
+  "dependencies": {
+    "package-1": "link:../package-1"
+  }
+}

commands/publish/__tests__/publish-command.test.js

@@ -1204,6 +1204,16 @@ describe("PublishCommand", () => {
         "package-6": "6.0.0",
       });
     });
+
+    it("works around npm-incompatible link: specifiers", async () => {
+      const testDir = await initFixture("yarn-link-spec");
+
+      await lernaPublish(testDir)("--cd-version", "major", "--yes");
+
+      expect(updatedPackageJSON("package-2").dependencies).toMatchObject({
+        "package-1": "^2.0.0",
+      });
+    });
   });
 
   describe("in a cyclical repo", () => {

core/package-graph/index.js

@@ -70,7 +70,11 @@ class PackageGraph extends Map {
 
       Object.keys(graphDependencies).forEach(depName => {
         const depNode = this.get(depName);
-        const resolved = npa.resolve(depName, graphDependencies[depName], currentNode.location);
+        // Yarn decided to ignore https://github.com/npm/npm/pull/15900 and implemented "link:"
+        // As they apparently have no intention of being compatible, we have to do it for them.
+        // @see https://github.com/yarnpkg/yarn/issues/4212
+        const spec = graphDependencies[depName].replace(/^link:/, "file:");
+        const resolved = npa.resolve(depName, spec, currentNode.location);
 
         if (!depNode) {
           // it's an external dependency, store the resolution and bail