dart language sever not working

[netsmertia]

Oni Version: version: 0.3.9 Neovim Version (Linux only): Operating System: macOS Mojave

Issue: Dart Language server not working.

Error: Unable to start language server process
    at ue.<anonymous> (vendor.bundle.js:127)
    at Generator.next (<anonymous>)
    at s (vendor.bundle.js:127)
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188)
t.error @ bundle.js:1
i._currentPromise.then.e @ vendor.bundle.js:816
_tickCallback @ internal/process/next_tick.js:188
Promise rejected (async)
enqueuePromise @ vendor.bundle.js:816
sendNotification @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:124
s @ vendor.bundle.js:124
_tickCallback @ internal/process/next_tick.js:188
Promise resolved (async)
c @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
sendLanguageServerNotification @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
_onBufferEnter @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
_oni.editors.anyEditor.onBufferEnter.subscribe @ vendor.bundle.js:124
emitOne @ events.js:121
emit @ events.js:211
dispatch @ vendor.bundle.js:632
e._subscriptions.e.onBufferEnter.subscribe.e @ vendor.bundle.js:1
emitOne @ events.js:121
emit @ events.js:211
dispatch @ vendor.bundle.js:632
notifyBufferEnter @ vendor.bundle.js:920
enter @ vendor.bundle.js:1252
enter @ 19.bundle.js:220
enter @ vendor.bundle.js:1
S.e.on @ vendor.bundle.js:1
apply @ /Applications/Oni.app/Contents/Resources/electron.asar/common/api/callbacks-registry.js:47
ipcRenderer.on @ /Applications/Oni.app/Contents/Resources/electron.asar/renderer/api/remote.js:277
emitMany @ events.js:147
emit @ events.js:224
bundle.js:1 [LanguageClientProcess] Ending language server session
bundle.js:1 [LanguageClientProcess]: Starting process via 'dart_language_server'
bundle.js:1 'LANG' environment variable not set, using default value of 'en_us.UTF-8'. Consider setting environment.additionalVariables['LANG'].
t.warn @ bundle.js:1
(anonymous) @ vendor.bundle.js:824
(anonymous) @ vendor.bundle.js:824
a @ vendor.bundle.js:824
mergeSpawnOptions.e @ vendor.bundle.js:824
(anonymous) @ vendor.bundle.js:824
(anonymous) @ vendor.bundle.js:824
a @ vendor.bundle.js:824
spawnProcess @ vendor.bundle.js:824
(anonymous) @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:127
ce @ vendor.bundle.js:127
_start @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:127
s @ vendor.bundle.js:127
_tickCallback @ internal/process/next_tick.js:188
Promise resolved (async)
c @ vendor.bundle.js:127
s @ vendor.bundle.js:127
_tickCallback @ internal/process/next_tick.js:188
Promise resolved (async)
c @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:127
ce @ vendor.bundle.js:127
ensureActive @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:127
ne @ vendor.bundle.js:127
_promiseQueue.enqueuePromise @ vendor.bundle.js:127
n @ vendor.bundle.js:816
i._currentPromise.then.e @ vendor.bundle.js:816
_tickCallback @ internal/process/next_tick.js:188
Promise rejected (async)
enqueuePromise @ vendor.bundle.js:816
sendNotification @ vendor.bundle.js:127
(anonymous) @ vendor.bundle.js:124
s @ vendor.bundle.js:124
_tickCallback @ internal/process/next_tick.js:188
Promise resolved (async)
c @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
sendLanguageServerNotification @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
_onBufferEnter @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
(anonymous) @ vendor.bundle.js:124
y @ vendor.bundle.js:124
_oni.editors.anyEditor.onBufferEnter.subscribe @ vendor.bundle.js:124
emitOne @ events.js:121
emit @ events.js:211
dispatch @ vendor.bundle.js:632
e._subscriptions.e.onBufferEnter.subscribe.e @ vendor.bundle.js:1
emitOne @ events.js:121
emit @ events.js:211
dispatch @ vendor.bundle.js:632
notifyBufferEnter @ vendor.bundle.js:920
enter @ vendor.bundle.js:1252
enter @ 19.bundle.js:220
enter @ vendor.bundle.js:1
S.e.on @ vendor.bundle.js:1
apply @ /Applications/Oni.app/Contents/Resources/electron.asar/common/api/callbacks-registry.js:47
ipcRenderer.on @ /Applications/Oni.app/Contents/Resources/electron.asar/renderer/api/remote.js:277
emitMany @ events.js:147
emit @ events.js:224
bundle.js:1 Error: spawn dart_language_server ENOENT
    at _errnoException (util.js:1024)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:190)
    at onErrorNT (internal/child_process.js:372)
    at _combinedTickCallback (internal/process/next_tick.js:138)
    at process._tickCallback (internal/process/next_tick.js:180)
t.error @ bundle.js:1
s.on.e @ vendor.bundle.js:824
emitOne @ events.js:116
emit @ events.js:211
ChildProcess._handle.onexit @ internal/child_process.js:196
onErrorNT @ internal/child_process.js:372
_combinedTickCallback @ internal/process/next_tick.js:138
_tickCallback @ internal/process/next_tick.js:180
bundle.js:1 Received notification for - Unhandled Rejection:Error: Unable to start language server process
Please report this error.
t.error @ bundle.js:1
t @ 22.bundle.js:1
d.onUnhandledRejection.subscribe.e @ 22.bundle.js:1
emitOne @ events.js:116
emit @ events.js:211
dispatch @ vendor.bundle.js:632
window.addEventListener.e @ 22.bundle.js:1
vendor.bundle.js:127 Uncaught (in promise) Error: Unable to start language server process
    at ue.<anonymous> (vendor.bundle.js:127)
    at Generator.next (<anonymous>)
    at s (vendor.bundle.js:127)
    at <anonymous>
    at process._tickCallback (internal/process/next_tick.js:188)
(anonymous) @ vendor.bundle.js:127
s @ vendor.bundle.js:127
_tickCallback @ internal/process/next_tick.js:188
Promise rejected (async)
_tickCallback @ internal/process/next_tick.js:188

here the screenshot of error in dev tools ( it is more readable)

I have fresh setup of neovim and oni (installed today) and no plugins in neovim config. Trying to switch to oni from vscode as it looks very promising.

[oni-bot[bot]]

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