fix: ignore invalid JSON in stdout

Author: pvdlg

README.md

@@ -63,11 +63,11 @@ Execute a shell command to prepare the release.
 
 Execute a shell command to publish the release.
 
-| Command property | Description                                                                                                                                               |
-|------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------|
-| `exit code`      | Any non `0` code is considered as an unexpected error and will stop the `semantic-release` execution with an error.                                       |
-| `stdout`         | Only the `release` information must be written to `stdout` as parseable JSON (for example `{"name": "Release name", "url": "http://url/release/1.0.0"}`). |
-| `stderr`         | Can be used for logging.                                                                                                                                  |
+| Command property | Description                                                                                                                                                                                                                                        |
+|------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| `exit code`      | Any non `0` code is considered as an unexpected error and will stop the `semantic-release` execution with an error.                                                                                                                                |
+| `stdout`         | The `release` information can be written to `stdout` as parseable JSON (for example `{"name": "Release name", "url": "http://url/release/1.0.0"}`). If the command write non parseable JSON to `stdout` no `release` information will be returned. |
+| `stderr`         | Can be used for logging.                                                                                                                                                                                                                           |
 
 ## success
 

index.js

@@ -1,5 +1,6 @@
 const {castArray, isPlainObject} = require('lodash');
 const parseJson = require('parse-json');
+const debug = require('debug')('semantic-release:exec');
 const SemanticReleaseError = require('@semantic-release/error');
 const execScript = require('./lib/exec-script');
 const verifyConfig = require('./lib/verify-config');
@@ -52,7 +53,15 @@ async function prepare(pluginConfig, params) {
 
 async function publish(pluginConfig, params) {
   const stdout = await execScript(pluginConfig, params);
-  return stdout.trim() ? parseJson(stdout) : undefined;
+  try {
+    return stdout.trim() ? parseJson(stdout) : undefined;
+  } catch (err) {
+    debug(stdout);
+    debug(err);
+    params.logger.log(
+      `The command ${pluginConfig.cmd} wrote invalid JSON to stdout. The stdout content will be ignored.`
+    );
+  }
 }
 
 async function success(pluginConfig, params) {

test/publish.test.js

@@ -24,24 +24,24 @@ test.serial('Parse JSON returned by publish script', async t => {
   t.deepEqual(result, {name: 'Release name', url: 'https://host.com/release/1.0.0'});
 });
 
-test.serial('Return "undefined" if the publish script wrtite nothing to stdout', async t => {
+test.serial('Return "undefined" if the publish script wrtite invalid JSON to stdout', async t => {
   const pluginConfig = {
-    cmd: './test/fixtures/echo-args.sh',
+    cmd: './test/fixtures/echo-args.sh invalid_json',
   };
   const params = {logger: t.context.logger};
 
   const result = await publish(pluginConfig, params);
   t.is(result, undefined);
 });
 
-test.serial('Throw JSONError if publish script write invalid JSON to stdout', async t => {
+test.serial('Return "undefined" if the publish script wrtite nothing to stdout', async t => {
   const pluginConfig = {
-    cmd: './test/fixtures/echo-args.sh invalid_json',
+    cmd: './test/fixtures/echo-args.sh',
   };
   const params = {logger: t.context.logger};
 
-  const error = await t.throws(publish(pluginConfig, params));
-  t.is(error.name, 'JSONError');
+  const result = await publish(pluginConfig, params);
+  t.is(result, undefined);
 });
 
 test.serial('Throw "Error" if the publish script does not returns 0', async t => {