fix: honor '-' when merging dependencies

src/extract-from-package.mjs

@@ -3,7 +3,7 @@ import { packageDirectory } from "pkg-dir";
 import { packageWalker } from "npm-package-walker";
 import { createContext } from "expression-expander";
 import { satisfies } from "compare-versions";
-import { asArray } from "./util.mjs";
+import { asArray, mergeDependencies } from "./util.mjs";
 import { NPMPackContentProvider } from "./content/npm-pack-content-provider.mjs";
 import { NodeModulesContentProvider } from "./content/node-modules-content-provider.mjs";
 import { FileContentProvider } from "./content/file-content-provider.mjs";
@@ -280,7 +280,7 @@ export async function* extractFromPackage(options = {}, env = {}) {
   )) {
     let arch = variant.arch;
     let properties = {};
-    const depends = {};
+    let depends = {};
     const output = {};
     const content = [];
 
@@ -312,7 +312,7 @@ export async function* extractFromPackage(options = {}, env = {}) {
       if (requirementsMet) {
         arch = new Set([...arch, ...fragment.arch]);
         properties = { ...fragment.properties, ...properties };
-        Object.assign(depends, fragment.depends);
+        depends = mergeDependencies(depends, fragment.depends);
         Object.assign(output, fragment.output);
         if (fragment.content) {
           content.push([fragment.content, fragment.dir]);

src/util.mjs

@@ -17,11 +17,24 @@ export const packageNameMapping = {
   node: "nodejs"
 };
 
-export function filterOutUnwantedDependencies()
-{
+export function filterOutUnwantedDependencies() {
   return ([name, version]) => version !== "-";
 }
 
+export function mergeDependencies(a, b) {
+  const keys = new Set([...Object.keys(a), ...Object.keys(b)]);
+
+  const result = {};
+
+  for (const key of keys) {
+    if (a[key] !== "-" && b[key] !== "-") {
+      result[key] = a[key] || b[key];
+    }
+  }
+
+  return result;
+}
+
 /**
  * Decode a password
  * @param {string} password

tests/merge-depencencies-ava.mjs

@@ -0,0 +1,14 @@
+import test from "ava";
+import { mergeDependencies } from "../src/util.mjs";
+
+test("mergeDependencies", t => {
+  const a = { a: "1.2.3" };
+  const b = { b: "3.4.5" };
+  t.deepEqual(mergeDependencies(a, b), { a: "1.2.3", b: "3.4.5" });
+});
+
+test("mergeDependencies remove", t => {
+  const a = { a: "1.2.3", a2: "1.0.0" };
+  const b = { a: "-" };
+  t.deepEqual(mergeDependencies(a, b), { a2: "1.0.0" });
+});