Improve error messages when bin version requirements are invalid (#457)

bin/compile

@@ -42,6 +42,9 @@ echo "" > "$LOG_FILE"
 handle_failure() {
   header "Build failed"
   fail_yarn_lockfile_outdated "$LOG_FILE"
+  fail_node_install "$LOG_FILE"
+  fail_yarn_install "$LOG_FILE"
+  fail_invalid_semver "$LOG_FILE"
   warn_untracked_dependencies "$LOG_FILE"
   warn_angular_resolution "$LOG_FILE"
   warn_missing_devdeps "$LOG_FILE"

lib/binaries.sh

@@ -15,7 +15,7 @@ install_yarn() {
 
   echo "Resolving yarn version ${version:-(latest)}..."
   if ! read number url < <(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=$version" "https://nodebin.herokai.com/v1/yarn/$platform/latest.txt"); then
-    echo "Unable to resolve; does that version exist?" && false
+    fail_bin_install yarn $version;
   fi
 
   echo "Downloading and installing yarn ($number)..."
@@ -41,7 +41,7 @@ install_nodejs() {
 
   echo "Resolving node version $version..."
   if ! read number url < <(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=$version" "https://nodebin.herokai.com/v1/node/$platform/latest.txt"); then
-    echo "Unable to resolve; does that version exist?" && false
+    fail_bin_install node $version;
   fi
 
   echo "Downloading and installing node $number..."
@@ -61,7 +61,7 @@ install_iojs() {
 
   echo "Resolving iojs version ${version:-(latest stable)}..."
   if ! read number url < <(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=$version" "https://nodebin.herokai.com/v1/iojs/$platform/latest.txt"); then
-    echo "Unable to resolve; does that version exist?" && false
+    fail_bin_install iojs $version;
   fi
 
   echo "Downloading and installing iojs $number..."

lib/failure.sh

@@ -123,7 +123,7 @@ fail_yarn_lockfile_outdated() {
     echo ""
     warn "Outdated Yarn lockfile
 
-       Your application contains a Yarn lockfile (yarn.lock) which does not 
+       Your application contains a Yarn lockfile (yarn.lock) which does not
        match the dependencies in package.json. This can happen if you use npm
        to install or update a dependency instead of Yarn.
 
@@ -139,6 +139,112 @@ fail_yarn_lockfile_outdated() {
   fi
 }
 
+fail_bin_install() {
+  local bin="$1"
+  local version="$2"
+
+  # re-curl the result, saving off the reason for the failure this time
+  local error=$(curl --silent --get --retry 5 --retry-max-time 15 --data-urlencode "range=$version" "https://nodebin.herokai.com/v1/$bin/$platform/latest.txt")
+
+  if [[ $error = "No result" ]]; then
+    case $bin in
+      node)
+        echo "Could not find Node version corresponding to version requirement: $version";;
+      iojs)
+        echo "Could not find Iojs version corresponding to version requirement: $version";;
+      yarn)
+        echo "Could not find Yarn version corresponding to version requirement: $version";;
+    esac
+  else
+    echo "Error: Invalid semantic version \"$version\""
+  fi
+
+  false
+}
+
+fail_node_install() {
+  local log_file="$1"
+  local node_engine=$(read_json "$BUILD_DIR/package.json" ".engines.node")
+
+  if grep -qi 'Could not find Node version corresponding to version requirement' "$log_file"; then
+    mcount "failures.invalid-node-version"
+    echo ""
+    warn "No matching version found for Node: $node_engine
+
+       Heroku supports the latest Stable version of Node.js as well as all
+       active LTS (Long-Term-Support) versions, however you have specified
+       a version in package.json ($node_engine) that does not correspond to
+       any published version of Node.js.
+
+       You should always specify a Node.js version that matches the runtime
+       you’re developing and testing with. To find your version locally:
+
+       $ node --version
+       v6.11.1
+
+       Use the engines section of your package.json to specify the version of
+       Node.js to use on Heroku. Drop the ‘v’ to save only the version number:
+
+       \"engines\": {
+         \"node\": \"6.11.1\"
+       }
+    " https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-no-matching-node-versions
+    exit 1
+  fi
+}
+
+fail_yarn_install() {
+  local log_file="$1"
+  local yarn_engine=$(read_json "$BUILD_DIR/package.json" ".engines.yarn")
+
+  if grep -qi 'Could not find Yarn version corresponding to version requirement' "$log_file"; then
+    mcount "failures.invalid-yarn-version"
+    echo ""
+    warn "No matching version found for Yarn: $yarn_engine
+
+       Heroku supports every version of Yarn published on npm, however you have
+       specified a version in package.json ($yarn_engine) that does not correspond
+       to any published version of Yarn. You can see a list of all published
+       versions of Yarn with the following command:
+
+       $ yarn info yarn versions
+
+       You should always specify a Yarn version that matches the version
+       you’re developing and testing with. To find your version locally:
+
+       $ yarn --version
+       0.27.5
+
+       Use the engines section of your package.json to specify the version of
+       Yarn to use on Heroku.
+
+       \"engines\": {
+         \"yarn\": \"0.27.5\"
+       }
+    " https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-no-matching-yarn-versions
+    exit 1
+  fi
+}
+
+fail_invalid_semver() {
+  local log_file="$1"
+  if grep -qi 'Error: Invalid semantic version' "$log_file"; then
+    mcount "failures.invalid-semver-requirement"
+    echo ""
+    warn "Invalid semver requirement
+
+       Node, Yarn, and npm adhere to semver, the semantic versioning convention
+       popularized by GitHub.
+
+       http://semver.org/
+
+       However you have specified a version requirement that is not a valid
+       semantic version.
+    " https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-an-invalid-semver-requirement
+    exit 1
+  fi
+}
+
 warning() {
   local tip=${1:-}
   local url=${2:-https://devcenter.heroku.com/articles/nodejs-support}

test/fixtures/invalid-node-semver/README.md

+A fake README, to keep npm from polluting stderr.
\ No newline at end of file

test/fixtures/invalid-node-semver/package.json

+{
+  "name": "node-buildpack-test-app",
+  "version": "0.0.1",
+  "description": "node buildpack integration test app",
+  "repository" : {
+    "type" : "git",
+    "url" : "http://github.com/example/example.git"
+  },
+  "dependencies": {
+  },
+  "engines": {
+    "node": "stable"
+  }
+}

test/fixtures/yarn-invalid-semver/package.json

+{
+  "name": "yarn",
+  "version": "1.0.0",
+  "main": "index.js",
+  "license": "MIT",
+  "engines": {
+    "yarn": "0.17q"
+  },
+  "dependencies": {
+    "lodash": "^4.16.4"
+  }
+}

test/fixtures/yarn-invalid-semver/yarn.lock

+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+lodash:
+  version "4.16.4"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.16.4.tgz#01ce306b9bad1319f2a5528674f88297aeb70127"
+

test/fixtures/yarn-invalid/package.json

+{
+  "name": "yarn",
+  "version": "1.0.0",
+  "main": "index.js",
+  "license": "MIT",
+  "engines": {
+    "yarn": "0.171"
+  },
+  "dependencies": {
+    "lodash": "^4.16.4"
+  }
+}

test/fixtures/yarn-invalid/yarn.lock

+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+lodash:
+  version "4.16.4"
+  resolved "https://registry.yarnpkg.com/lodash/-/lodash-4.16.4.tgz#01ce306b9bad1319f2a5528674f88297aeb70127"
+

test/run

@@ -89,6 +89,24 @@ testYarnSemver() {
   assertCapturedSuccess
 }
 
+testYarnInvalid() {
+  compile "yarn-invalid"
+  assertCaptured "Resolving yarn version 0.171"
+  assertCaptured "Could not find Yarn version corresponding to version requirement: 0.171"
+  assertCaptured "No matching version found for Yarn: 0.171"
+  assertCaptured "https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-no-matching-yarn-versions"
+  assertCapturedError
+}
+
+testYarnSemverInvalid() {
+  compile "yarn-invalid-semver"
+  assertCaptured "Resolving yarn version 0.17q"
+  assertCaptured "Error: Invalid semantic version \"0.17q\""
+  assertCaptured "Invalid semver requirement"
+  assertCaptured "https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-an-invalid-semver-requirement"
+  assertCapturedError
+}
+
 testYarnRun() {
   compile "yarn-run"
   assertCaptured "Running heroku-postbuild (yarn)"
@@ -345,14 +363,24 @@ testConcurrencyCustomLimit() {
 testInvalidNode() {
   compile "invalid-node"
   assertCaptured "Resolving node version 0.11.333"
-  assertCaptured "Unable to resolve"
+  assertCaptured "Could not find Node version corresponding to version requirement: 0.11.333"
+  assertCaptured "No matching version found for Node: 0.11.333"
+  assertCaptured "https://kb.heroku.com/why-is-my-node-js-build-failing-because-of-no-matching-node-versions"
+  assertCapturedError
+}
+
+testInvalidNodeSemver() {
+  compile "invalid-node-semver"
+  assertCaptured "Resolving node version stable"
+  assertCaptured "Error: Invalid semantic version \"stable\""
+  assertCaptured "Invalid semver requirement"
   assertCapturedError
 }
 
 testInvalidIo() {
   compile "invalid-io"
   assertCaptured "Resolving iojs version 2.0.99"
-  assertCaptured "Unable to resolve"
+  assertCaptured "Could not find Iojs version corresponding to version requirement: 2.0.99"
   assertCapturedError
 }