Utils `gatherSources` fails if path has spaces

[spalladino]

The gatherSources script relies on url.resolve to resolve absolute paths. This changes any spaces in a local filesystem path to %20, which then fails to find the file.

resolver-engine/packages/imports/src/utils.ts

Line 108 in aa15ba1

const absoluteRoots = roots.map(what => urlSys.resolve(workingDir, what));

[spalladino]

FWIW, we have fixed this replacing all calls to urlSys.resolve by calls to the following function:

import isUrl from 'is-url';
function resolvePath(workingDir: string, relativePath: string): string {
  // If the working dir is an URL (a file imported from an URL location)
  // or the relative path is an URL (an URL imported from a local file)
  // use url.resolve, which will work in both cases.
  // > url.resolve('/local/folder/', 'http://example.com/myfile.sol')
  // 'http://example.com/myfile.sol'
  // > url.resolve('http://example.com/', 'myfile.sol')
  // 'http://example.com/myfile.sol'
  //
  // If not, use path.resolve, since using url.resolve will escape certain
  // charaters (e.g. a space as an %20), breaking the path
  // > url.resolve('/local/path/with spaces/', 'myfile.sol')
  // '/local/path/with%20spaces/myfile.sol'

  return isUrl(workingDir) || isUrl(relativePath)
    ? urlSys.resolve(workingDir, relativePath)
    : pathSys.resolve(path.dirname(workingDir), relativePath);
}

[ritave]

@spalladino Heads up, doing just this makes the gatherSources tests break, see #187 for details.