fix(verify-conditions): Added check for non existant package name

re #4

README.md

@@ -69,9 +69,10 @@ Installing the app will yield you with a webhook that the app uses to publish up
 
 The `SLACK_WEBHOOK` variable has to be defined in the environment where you will be running semantic release. This can be done by exporting it in bash or in the user interface of you CI provider. Obtain this token by installing the slack app according to [slack app installation](#slack-app-installation).
 
-| Variable        | Description                                         |
-| --------------- | --------------------------------------------------- |
-| `SLACK_WEBHOOK` | Slack webhook created when adding app to workspace. |
+| Variable                   | Description                                              |
+| -------------------------- | -------------------------------------------------------- |
+| `SLACK_WEBHOOK`            | Slack webhook created when adding app to workspace.      |
+| `SEMANTIC_RELEASE_PACKAGE` | Override or add package name instead of npm package name |
 
 ### Options
 

lib/success.js

@@ -3,7 +3,9 @@ const postMessage = require('./postMessage')
 
 module.exports = async (pluginConfig, context) => {
 	const { logger, nextRelease, options } = context
-	const { npm_package_name } = context.env
+
+	let package_name = context.env.SEMANTIC_RELEASE_PACKAGE
+	if (!package_name) package_name = context.env.npm_package_name
 
 	if (!pluginConfig.notifyOnSuccess) {
 		logger.log('Notifying on success skipped')
@@ -17,7 +19,7 @@ module.exports = async (pluginConfig, context) => {
 			type: 'section',
 			text: {
 				type: 'mrkdwn',
-				text: `A new version of \`${npm_package_name}\` has been released!\nCurrent version is *#${
+				text: `A new version of \`${package_name}\` has been released!\nCurrent version is *#${
 					nextRelease.version
 				}*`
 			}
@@ -36,7 +38,7 @@ module.exports = async (pluginConfig, context) => {
 
 	let slackMessage = {
 		blocks: messageBlocks,
-		text: `A new version of ${npm_package_name} has been released!`
+		text: `A new version of ${package_name} has been released!`
 	}
 
 	if (options.repositoryUrl.indexOf('[email protected]') !== -1) {

lib/verifyConditions.js

@@ -13,4 +13,18 @@ module.exports = (pluginConfig, context) => {
 			`A Slack Webhook must be created and set in the \`SLACK_WEBHOOK\` environment variable on your CI environment.\n\n\nPlease make sure to create a Slack Webhook and to set it in the \`SLACK_WEBHOOK\` environment variable on your CI environment.`
 		)
 	}
+
+	if (
+		!context.env.npm_package_name &&
+		!context.env.SEMANTIC_RELEASE_PACKAGE
+	) {
+		logger.log(
+			'npm package name and SEMANTIC_RELEASE_PACKAGE name are undefined'
+		)
+		throw new SemanticReleaseError(
+			'No name for the package defined.',
+			'ENOPACKAGENAME',
+			`A name for the package must be created. Run through npm (npm run <semantic-release-script> to use npm package name or define \`SEMANTIC_RELEASE_PACKAGE\` in the environment`
+		)
+	}
 }