gatsby bulid errors

[rdela]

On node 9.6.1, npm v5.6.0, and yarn 1.3.2, I just had to pin both

"gatsby": "1.9.212",
"gatsby-plugin-netlify-cms": "1.0.8",

…on an experiment based on the Gatsby + Netlify CMS Starter to get build working.

Various errors on local build and newer Gatsby:

error You used a reserved field name in the context object when creating a page:

  * "path"

{
    "path": "about",
    "component": "/Users/[…]/src/templates/about-page.js",
    "context": {
        "path": "about"
    }
}

Data in "context" is passed to GraphQL as potential arguments when running the
page query.

When arguments for GraphQL are constructed, the context object is combined with
the page object so both page object and context data are available as
arguments. If a context field duplicates a field already used by the page
object, this can break functionality within Gatsby so must be avoided.

Please choose another name for the conflicting fields.

The following fields are used by the page object and must be avoided.

  * "path"
  * "matchPath"
  * "component"
  * "componentChunkName"
  * "pluginCreator___NODE"
  * "pluginCreatorName"

…and remote bulid errors like:

12:16:18 PM: success Building CSS — 15.913 s
12:17:30 PM: error Generating JavaScript bundles failed
12:17:30 PM: 
12:17:30 PM:   Error: app-44c0ec4e989ce3631b16.js from UglifyJs
12:17:30 PM:   SyntaxError: Unexpected character '`' [./~/gatsby-plugin-netlify-cms/gatsby-br  owser.js:10,0]
12:17:30 PM: 
12:17:30 PM: npm
12:17:30 PM:  ERR! code ELIFECYCLE
12:17:30 PM: npm ERR! errno 1
12:17:30 PM: npm ERR! [email protected] build: `gatsby build`
12:17:30 PM: npm ERR! Exit status 1
12:17:30 PM: npm ERR!
12:17:30 PM: npm ERR! Failed at the [email protected] build script.

Maybe an underlying issue from #1097 persists? Cc @tech4him1 @erquhart

[rdela]

related gatsbyjs/gatsby#4233

[erquhart]

This has been fixed in the starter, the context object just needs to be removed.