test and implementation for unmet dependencies

bin/compile

@@ -162,3 +162,4 @@ header "Build succeeded!"
 summarize_build | output "$LOG_FILE"
 
 warn_no_start "$LOG_FILE"
+warn_unmet_dep "$LOG_FILE"

lib/failure.sh

@@ -128,3 +128,10 @@ warn_econnreset() {
     warning "ECONNRESET issues may be related to npm versions" "https://github.com/npm/registry/issues/10#issuecomment-217141066"
   fi
 }
+
+warn_unmet_dep() {
+  local log_file="$1"
+  if grep -qi 'unmet dependency' "$log_file" || grep -qi 'unmet peer dependency' "$log_file"; then
+    warn "Unmet dependencies don't fail npm install but may cause runtime issues" "https://github.com/npm/npm/issues/7494"
+  fi
+}

test/fixtures/unmet-dep/package.json

+{
+  "name": "unmet-dep",
+  "version": "1.0.0",
+  "description": "",
+  "main": "index.js",
+  "scripts": {
+    "start": "node server.js"
+  },
+  "keywords": [],
+  "author": "",
+  "license": "ISC",
+  "dependencies": {
+    "grunt-steroids": "0.2.3"
+  }
+}

test/run

 #!/usr/bin/env bash
 # See README.md for info on running these tests.
 
+testWarnUnmetDep() {
+  compile "unmet-dep"
+  assertCaptured "may cause runtime issues"
+  assertCapturedSuccess
+  compile "no-version"
+  assertNotCaptured "may cause runtime issues"
+  assertCapturedSuccess
+}
+
 testWarnEconnreset() {
   compile "econnreset-mock"
   assertCaptured "may be related to npm versions"