Traceback on dependency resolution error with editable git 
When I have an editable git repository and another requirement that causes a dependency resolution failure in my Pipfile, I get a `FileNotFoundError: [Errno 2] No such file or directory: '"/usr/bin/python3"': '"/usr/bin/python3"'` error.

My reproducer uses https://github.com/OddBloke/sphinx-git and python-novaclient==2.26.0 (which always causes a dependency resolution error, as mentioned in #1232).

(As far as I can tell, the git repository and the other requirement don't need to be at all related to end up with this traceback.)

##### Describe your environment

1. OS Type: Ubuntu 17.10
1. Python version: Python 3.6.3
1. Pipenv version: pipenv, version 9.0.1

##### Expected result

Dependency resolution error output, with no traceback.

##### Actual result

A traceback:

```pytb
Traceback (most recent call last):
  File "/home/daniel/.local/bin/pipenv", line 11, in <module>
    sys.exit(cli())
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1865, in install
    do_init(dev=dev, allow_global=system, ignore_pipfile=ignore_pipfile, system=system, skip_lock=skip_lock, verbose=verbose, concurrent=concurrent, deploy=deploy, pre=pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1311, in do_init
    do_lock(system=system, pre=pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1102, in do_lock
    pre=pre
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/utils.py", line 557, in resolve_deps
    resolved_tree = actually_resolve_reps(deps, index_lookup, markers_lookup, project, sources, verbose, clear, pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/utils.py", line 507, in actually_resolve_reps
    resolved_tree.update(resolver.resolve(max_rounds=PIPENV_MAX_ROUNDS))
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 102, in resolve
    has_changed, best_matches = self._resolve_one_round()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 200, in _resolve_one_round
    for dep in self._iter_dependencies(best_match):
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 274, in _iter_dependencies
    for dependency in self.repository.get_dependencies(ireq):
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/repositories/pypi.py", line 153, in get_dependencies
    result = reqset._prepare_file(self.finder, ireq)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_set.py", line 523, in _prepare_file
    abstract_dist.prep_for_dist()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_set.py", line 134, in prep_for_dist
    self.req_to_install.run_egg_info()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_install.py", line 438, in run_egg_info
    command_desc='python setup.py egg_info')
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/utils/__init__.py", line 667, in call_subprocess
    cwd=cwd, env=env)
  File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: '"/usr/bin/python3"': '"/usr/bin/python3"'
```

##### Steps to replicate

1. Put this in a Pipfile:
```
[[source]]

url = "https://pypi.python.org/simple"
verify_ssl = true
name = "pypi"


[packages]

sphinx-git = {git = "https://github.com/OddBloke/sphinx-git.git", editable = true}
python-novaclient = "~=2.26.0"

[dev-packages]
```
2. Run `pipenv install`.

```
$ pipenv install --verbose
Pipfile.lock not found, creating…
Locking [dev-packages] dependencies…
Locking [packages] dependencies…
Warning: Your dependencies could not be resolved. You likely have a mismatch in your sub-dependencies.
  You can use $ pipenv install --skip-lock to bypass this mechanism, then run $ pipenv graph to inspect the situation.
Could not find a version that matches pbr!=2.1.0,<2.0,>=0.11,>=2.0.0
Tried: 0.5.2.5.g5b3e942, 0.5.0, 0.5.1, 0.5.2, 0.5.4, 0.5.5, 0.5.6, 0.5.7, 0.5.8, 0.5.10, 0.5.11, 0.5.12, 0.5.13, 0.5.14, 0.5.15, 0.5.16, 0.5.17, 0.5.18, 0.5.19, 0.5.20, 0.5.21, 0.5.22, 0.5.23, 0.6, 0.7.0, 0.8.0, 0.8.1, 0.8.2, 0.9.0, 0.9.0, 0.10.0, 0.10.0, 0.10.1, 0.10.1, 0.10.2, 0.10.2, 0.10.3, 0.10.3, 0.10.4, 0.10.4, 0.10.5, 0.10.5, 0.10.6, 0.10.6, 0.10.7, 0.10.7, 0.10.8, 0.10.8, 0.11.0, 0.11.0, 0.11.1, 0.11.1, 1.0.0, 1.0.0, 1.0.1, 1.0.1, 1.1.0, 1.1.0, 1.1.1, 1.1.1, 1.2.0, 1.2.0, 1.3.0, 1.3.0, 1.4.0, 1.4.0, 1.5.0, 1.5.0, 1.6.0, 1.6.0, 1.7.0, 1.7.0, 1.8.0, 1.8.0, 1.8.1, 1.8.1, 1.9.0, 1.9.0, 1.9.1, 1.9.1, 1.10.0, 1.10.0, 2.0.0, 2.0.0, 2.1.0, 2.1.0, 3.0.0, 3.0.0, 3.0.1, 3.0.1, 3.1.0, 3.1.0, 3.1.1, 3.1.1
CRITICAL:pip.utils:Error [Errno 2] No such file or directory: '"/usr/bin/python3"': '"/usr/bin/python3"' while executing command python setup.py egg_info
Traceback (most recent call last):
  File "/home/daniel/.local/bin/pipenv", line 11, in <module>
    sys.exit(cli())
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 722, in __call__
    return self.main(*args, **kwargs)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/vendor/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1865, in install
    do_init(dev=dev, allow_global=system, ignore_pipfile=ignore_pipfile, system=system, skip_lock=skip_lock, verbose=verbose, concurrent=concurrent, deploy=deploy, pre=pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1311, in do_init
    do_lock(system=system, pre=pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/cli.py", line 1102, in do_lock
    pre=pre
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/utils.py", line 557, in resolve_deps
    resolved_tree = actually_resolve_reps(deps, index_lookup, markers_lookup, project, sources, verbose, clear, pre)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/utils.py", line 507, in actually_resolve_reps
    resolved_tree.update(resolver.resolve(max_rounds=PIPENV_MAX_ROUNDS))
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 102, in resolve
    has_changed, best_matches = self._resolve_one_round()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 200, in _resolve_one_round
    for dep in self._iter_dependencies(best_match):
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/resolver.py", line 274, in _iter_dependencies
    for dependency in self.repository.get_dependencies(ireq):
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/piptools/repositories/pypi.py", line 153, in get_dependencies
    result = reqset._prepare_file(self.finder, ireq)
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_set.py", line 523, in _prepare_file
    abstract_dist.prep_for_dist()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_set.py", line 134, in prep_for_dist
    self.req_to_install.run_egg_info()
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/req/req_install.py", line 438, in run_egg_info
    command_desc='python setup.py egg_info')
  File "/home/daniel/.local/lib/python3.6/site-packages/pipenv/patched/pip/utils/__init__.py", line 667, in call_subprocess
    cwd=cwd, env=env)
  File "/usr/lib/python3.6/subprocess.py", line 709, in __init__
    restore_signals, start_new_session)
  File "/usr/lib/python3.6/subprocess.py", line 1344, in _execute_child
    raise child_exception_type(errno_num, err_msg, err_filename)
FileNotFoundError: [Errno 2] No such file or directory: '"/usr/bin/python3"': '"/usr/bin/python3"'
```
diff --git a/pipenv/utils.py b/pipenv/utils.py
index 29765eba..e7e8d0b2 100644
--- a/pipenv/utils.py
+++ b/pipenv/utils.py
@@ -516,7 +516,7 @@ def actually_resolve_reps(deps, index_lookup, markers_lookup, project, sources,
             ),
             err=True)
 
-        click.echo(crayons.blue(e))
+        click.echo(crayons.blue(str(e)))
 
         if 'no version found at all' in str(e):
             click.echo(crayons.blue('Please check your version specifier and version number. See PEP440 for more information.'))
@@ -535,7 +535,7 @@ def resolve_deps(deps, which, which_pip, project, sources=None, verbose=False, p
     markers_lookup = {}
 
     python_path = which('python', allow_global=allow_global)
-    backup_python_path = shellquote(sys.executable)
+    backup_python_path = sys.executable
 
     results = []
 
diff --git a/tests/test_pipenv.py b/tests/test_pipenv.py
index e973deb3..2afec23b 100644
--- a/tests/test_pipenv.py
+++ b/tests/test_pipenv.py
@@ -440,6 +440,30 @@ tablib = "<0.12"
             assert 'tablib' in p.lockfile['default']
 
 
+    @pytest.mark.e
+    @pytest.mark.install
+    @pytest.mark.vcs
+    @pytest.mark.resolver
+    def test_editable_vcs_install_in_pipfile_with_dependency_resolution_doesnt_traceback(self):
+        # See https://github.com/pypa/pipenv/issues/1240
+        with PipenvInstance() as p:
+            with open(p.pipfile_path, 'w') as f:
+                contents = """
+[packages]
+pypa-docs-theme = {git = "https://github.com/pypa/pypa-docs-theme", editable = true}
+
+# This version of requests depends on idna<2.6, forcing dependency resolution
+# failure
+requests = "==2.16.0"
+idna = "==2.6.0"
+                """.strip()
+                f.write(contents)
+            c = p.pipenv('install')
+            assert c.return_code == 1
+            assert "Your dependencies could not be resolved" in c.err
+            assert 'Traceback' not in c.err
+
+
     @pytest.mark.run
     @pytest.mark.install
     def test_multiprocess_bug_and_install(self):
['tests/test_pipenv.py', 'pipenv/utils.py']