fix(ci): disable preload when NODE_ENV is 'test'

Preload tests failed in browser because preload is enabled in browser
context by default and while js-ipfs tests disable preload in tests,
interface-ipfs-core does not.

This means interface-ipfs-core tests triggered dozens of slow/hanging
requests to `nodeX.preload.iofs.io/api/v0/refs` and js-ipfs executed
only 4 at a time. By the time preload tests got executed, the queue was
long and it did not finish before timeout.

This change detects js-ipfs is running in test environment
(`process.env.NODE_ENV === 'test'`) and disables preload by default.

This way we are still be able to test preload by explicitly enabling it
in config, but we won't have preload overhead when running unrelated
interface-ipfs-core tests.

License: MIT
Signed-off-by: Marcin Rataj <lidel@lidel.org>

src/cli/commands/daemon.js

@@ -31,7 +31,7 @@ module.exports = {
       })
       .option('enable-preload', {
         type: 'boolean',
-        default: true
+        default: process.env.NODE_ENV !== 'test' // preload by default, unless in test env
       })
   },
 

src/core/config.js

@@ -31,7 +31,10 @@ const configSchema = s({
     enabled: 'boolean?',
     addresses: optional(s(['multiaddr'])),
     interval: 'number?'
-  }, { enabled: true, interval: 30 * 1000 }),
+  }, { // defaults if missing:
+    enabled: process.env.NODE_ENV !== 'test', // preload by default, unless in test env
+    interval: 30 * 1000
+  }),
   init: optional(union(['boolean', s({
     bits: 'number?',
     emptyRepo: 'boolean?',

src/core/index.js

@@ -45,7 +45,7 @@ class IPFS extends EventEmitter {
       start: true,
       EXPERIMENTAL: {},
       preload: {
-        enabled: true,
+        enabled: process.env.NODE_ENV !== 'test', // preload by default, unless in test env
         addresses: [
           '/dnsaddr/node0.preload.ipfs.io/https',
           '/dnsaddr/node1.preload.ipfs.io/https'