refactor: better tree shaping

colours.ts

@@ -2,6 +2,8 @@ import {
   blue,
   cyan,
   gray,
+  green,
+  red,
   yellow,
 } from "https://deno.land/[email protected]/fmt/colors.ts";
 
@@ -12,6 +14,8 @@ export const colour = {
   file: cyan,
   subdued: gray,
   version: yellow,
+  valid: green,
+  invalid: red,
 };
 
 export const format = (name: string, range: Range) =>

fetch_peer_dependencies.test.ts

@@ -14,7 +14,8 @@ Deno.test("Can get peer dependencies", async () => {
     {
       name: "@guardian/core-web-vitals",
       range: new Range("2.0.2"),
-      versions: [new SemVer("2.0.2")],
+      version: new SemVer("2.0.2"),
+      dependencies: [],
       peers: [
         {
           name: "@guardian/libs",
@@ -50,7 +51,8 @@ Deno.test("Can get optional peer dependencies", async () => {
     {
       name: "@guardian/libs",
       range: new Range("12.0.0"),
-      versions: [new SemVer("12.0.0")],
+      version: new SemVer("12.0.0"),
+      dependencies: [],
       peers: [
         {
           name: "tslib",
@@ -78,7 +80,8 @@ Deno.test("Will fail on optional dependencies that are defined locally", async (
     {
       name: "@guardian/libs",
       range: new Range("12.0.0"),
-      versions: [new SemVer("12.0.0")],
+      version: new SemVer("12.0.0"),
+      dependencies: [],
       peers: [
         {
           name: "tslib",
@@ -95,13 +98,15 @@ Deno.test("Will fail on optional dependencies that are defined locally", async (
     {
       name: "tslib",
       range: new Range("2.4.1"),
-      versions: [new SemVer("2.4.1")],
+      version: new SemVer("2.4.1"),
+      dependencies: [],
       peers: [],
     },
     {
       name: "typescript",
       range: new Range("4.2.2"),
-      versions: [new SemVer("4.2.2")],
+      version: new SemVer("4.2.2"),
+      dependencies: [],
       peers: [],
     },
   ]);

fetch_peer_dependencies.ts

@@ -24,7 +24,7 @@ const { parseAsync: parse_peers } = object({
 
 export const fetch_peer_dependencies = (
   dependencies: Dependency[],
-  { verbose = false, cache = false } = {},
+  { cache = false } = {},
 ): Promise<RegistryDependency[]> =>
   Promise.all(
     dependencies.map((dependency) =>
@@ -38,20 +38,12 @@ export const fetch_peer_dependencies = (
         .then((res) => res.json())
         .then(parse_peers)
         .then((registry) => {
-          const [version, ...versions] = Object.values(registry.versions)
-            .filter(({ version }) => satisfies(version, dependency.range));
+          const version = Object.values(registry.versions)
+            .find(({ version }) => satisfies(version, dependency.range));
 
           if (!version) {
             throw new Error(
-              `Could not find ${dependency.name}@${dependency.range.range}`,
-            );
-          }
-
-          if (verbose && Object.keys(version.dependencies ?? {}).length > 0) {
-            console.warn(
-              `🔍 ${
-                format(dependency.name, dependency.range)
-              } – futher deps not analysed`,
+              `Could not find ${format(dependency.name, dependency.range)}`,
             );
           }
 
@@ -87,10 +79,13 @@ export const fetch_peer_dependencies = (
 
           return ({
             ...dependency,
+            dependencies: Object.entries(
+              version.dependencies ?? {},
+            ).map((
+              [name, range],
+            ) => ({ name, range: new Range(range) })),
             peers,
-            versions: [version, ...versions].map(({ version }) =>
-              new SemVer(version)
-            ),
+            version: new SemVer(version.version),
           });
         })
         .catch((error) => {

find_mismatches.test.ts

@@ -8,7 +8,8 @@ Deno.test("Works when all dependencies are matched", () => {
       {
         name: "one",
         range: new Range("1.0.0"),
-        versions: [new SemVer("1.0.0")],
+        version: new SemVer("1.0.0"),
+        dependencies: [],
         peers: [
           {
             name: "two",
@@ -25,7 +26,8 @@ Deno.test("Works when all dependencies are matched", () => {
       {
         name: "two",
         range: new Range("2.0.2"),
-        versions: [new SemVer("2.0.2")],
+        version: new SemVer("2.0.2"),
+        dependencies: [],
         peers: [
           { name: "four", satisfied: true, range: new Range("^4") },
         ],
@@ -41,7 +43,8 @@ Deno.test("Fails on invalid range", () => {
       {
         name: "one",
         range: new Range("1.0.0"),
-        versions: [new SemVer("1.0.0")],
+        version: new SemVer("1.0.0"),
+        dependencies: [],
         peers: [
           {
             name: "two",
@@ -53,7 +56,8 @@ Deno.test("Fails on invalid range", () => {
       {
         name: "two",
         range: new Range("2.0.2"),
-        versions: [new SemVer("2.0.2")],
+        version: new SemVer("2.0.2"),
+        dependencies: [],
         peers: [],
       },
     ]),

find_mismatches.ts

@@ -3,40 +3,45 @@ import { RegistryDependency } from "./types.ts";
 
 export const count_unsatisfied_peer_dependencies = (
   dependencies: RegistryDependency[],
-  verbose = true,
 ) =>
-  dependencies.map(({ name, range, peers }) => {
-    if (peers.length === 0) return 0;
+  dependencies.map(({ peers }) =>
+    peers.filter((peer) => !peer.satisfied).length
+  )
+    .reduce((acc, curr) => acc + curr);
 
-    const { length: unsatisfied } = peers.filter((peer) => !peer.satisfied);
+export const format_dependencies = (
+  dependencies: RegistryDependency[],
+  verbose = true,
+): void => {
+  dependencies.map(({ name, range, dependencies, peers }) => {
+    console.info(
+      `├─ ${format(name, range)}`,
+    );
 
-    if (unsatisfied === 0) {
-      if (verbose) {
-        console.info(
-          `✅ ${format(name, range)} – all ${
-            colour.file("peerDependencies")
-          } satisfied`,
-        );
-      }
-      return 0;
+    let count = dependencies.length;
+    for (const dependency of dependencies) {
+      const angle = peers.length === 0 && --count === 0 ? "╰" : "├";
+      console.warn(
+        `│  ${angle}─ ${colour.version("▲")} ${
+          format(dependency.name, dependency.range)
+        } – futher ${colour.file("dependencies")} not analysed`,
+      );
     }
 
-    console.error(
-      `🚨 ${format(name, range)} – unsatisfied ${
-        colour.file("peerDependencies")
-      }`,
-    );
-
+    count = peers.length;
     for (const { name, range, satisfied } of peers) {
+      const angle = --count === 0 ? "╰" : "├";
       if (satisfied) {
         if (verbose) {
-          console.info(`   - ✅ ${format(name, range)}`);
+          console.info(
+            `│  ${angle}─ ${colour.valid("○")} ${format(name, range)}`,
+          );
         }
       } else {
         console.error(
-          `   - 🚨 ${format(name, range)}`,
+          `│  ${angle}─ ${colour.invalid("✕")} ${format(name, range)}`,
         );
       }
     }
-    return unsatisfied;
-  }).reduce((acc, curr) => acc + curr);
+  });
+};

fixtures/package.json

@@ -1,4 +1,6 @@
 {
+  "name": "npm-dependencies",
+  "version": "0.0.1",
   "dependencies": {
     "@guardian/source-foundations": "8.0.0",
     "@guardian/core-web-vitals": "2.0.2"

fixtures/package_valid.json

@@ -1,4 +1,6 @@
 {
+  "name": "npm-dependencies",
+  "version": "0.0.1",
   "dependencies": {
     "@guardian/ab-core": "2.0.0",
     "@guardian/core-web-vitals": "2.0.2",

main.ts

@@ -1,7 +1,13 @@
-import { parse_declared_dependencies } from "./parse_dependencies.ts";
+import {
+  parse_declared_dependencies,
+  parse_package_info,
+} from "./parse_dependencies.ts";
 import { fetch_peer_dependencies } from "./fetch_peer_dependencies.ts";
-import { colour } from "./colours.ts";
-import { count_unsatisfied_peer_dependencies } from "./find_mismatches.ts";
+import { colour, format } from "./colours.ts";
+import {
+  count_unsatisfied_peer_dependencies,
+  format_dependencies,
+} from "./find_mismatches.ts";
 import { parse } from "https://deno.land/[email protected]/flags/mod.ts";
 
 const { _: [package_file], verbose, cache } = parse(Deno.args, {
@@ -15,41 +21,55 @@ if (typeof package_file !== "string") {
 
 const filename = Deno.cwd() + "/" + package_file;
 
-const package_content = await Deno.readTextFile(filename).catch(() => "");
+const package_content: unknown = await Deno.readTextFile(filename).catch(() =>
+  ""
+).then(
+  (contents) => JSON.parse(contents),
+);
 
-if (package_content) {
-  if (verbose) console.info(`✅ Found package.json file`);
-} else {
+if (!package_content) {
   console.error("🚨 No package.json found at", colour.file(filename));
   Deno.exit(1);
 }
 
-const dependencies = parse_declared_dependencies(package_content);
+const { name, range } = parse_package_info(package_content);
+
+console.info(`${format(name, range)}`);
 
-if (dependencies.length === 0) {
+const dependencies_from_package = parse_declared_dependencies(package_content);
+
+if (dependencies_from_package.length === 0) {
   if (verbose) {
     console.info("✅ You have no dependencies and therefore no issues!");
   }
   Deno.exit();
 }
 
-const dependencies_with_peers = await fetch_peer_dependencies(
-  dependencies,
-  { verbose, cache },
+const dependencies_from_registry = await fetch_peer_dependencies(
+  dependencies_from_package,
+  { cache },
 );
 
-const number_of_mismatched_deps = count_unsatisfied_peer_dependencies(
-  dependencies_with_peers,
+format_dependencies(
+  dependencies_from_registry,
   verbose,
 );
 
+const number_of_mismatched_deps = count_unsatisfied_peer_dependencies(
+  dependencies_from_registry,
+);
+
 if (number_of_mismatched_deps === 0) {
-  if (verbose) console.info("✅ Everything is fine with your dependencies");
+  if (verbose) console.info("✅ Dependencies are in good shape");
+} else if (number_of_mismatched_deps === 1) {
+  console.error(
+    `🚨 There is ${colour.file("1")} dependencies problem`,
+  );
 } else {
-  console.info(
+  console.error(
     `🚨 There are ${
       colour.file(String(number_of_mismatched_deps))
-    } unsatisfied peer dependencies`,
+    } dependencies problems`,
   );
 }
 

parse_dependencies.ts

@@ -27,9 +27,21 @@ const find_duplicates = (deps: Dependency[]): string[] => {
   return [...duplicates];
 };
 
-export const parse_declared_dependencies = (contents: string): Dependency[] => {
+const package_parser = object({
+  name: string(),
+  version: string(),
+});
+
+export const parse_package_info = (contents: unknown): Dependency => {
+  const { name, version } = package_parser.parse(contents);
+  return { name, range: new Range(version) };
+};
+
+export const parse_declared_dependencies = (
+  contents: unknown,
+): Dependency[] => {
   const { dependencies = {}, devDependencies = {} } = parse(
-    JSON.parse(contents),
+    contents,
   );
 
   for (

types.ts

@@ -6,7 +6,8 @@ export interface Dependency {
 }
 
 export interface RegistryDependency extends Dependency {
-  versions: SemVer[];
+  version: SemVer;
+  dependencies: Dependency[]
   peers: PeerDependency[];
 }