Fix #961 tests for Vim 7.4 (#990)

Use build stages to group related jobs (Vim, Neovim, Vim 7.4).
Use "silent" to avoid hit-enter prompt when redirecting output.
Always run async and sync tests to debug runtime errors. 
Vim 7.4.0052 (Ubuntu Trusty) does not allow dynamic keys in inline dictionary.

https://docs.travis-ci.com/user/build-stages/

.travis.yml

@@ -3,31 +3,40 @@ env:
   global:
     - DEPS=$HOME/deps
     - PATH=$DEPS/bin:$PATH
-matrix:
+jobs:
   include:
     - env: ENV=vim80-bionic
       dist: bionic
+      stage: vim8
     - env: ENV=vim-nightly
       dist: trusty
+      stage: vim8
     - env: ENV=neovim-stable
       dist: xenial
       addons: {apt: {packages: [neovim], sources: [{sourceline: 'ppa:neovim-ppa/stable'}]}}
+      stage: neovim
     - env: ENV=neovim-nightly
       dist: xenial
       addons: {apt: {packages: [neovim], sources: [{sourceline: 'ppa:neovim-ppa/unstable'}]}}
+      stage: neovim
     - env: ENV=vim74-trusty-python
       dist: trusty
+      stage: vim74
     - env: ENV=vim74-xenial-python3
       dist: xenial
+      stage: vim74
     - env: ENV=vim74-trusty-ruby
       dist: trusty
       addons: {apt: {packages: [vim-nox]}}
+      stage: vim74
     - env: ENV=vim74-xenial-ruby
       dist: xenial
       addons: {apt: {packages: [vim-nox]}}
+      stage: vim74
     - env: ENV=osx-highsierra
       os: osx
       osx_image: xcode9.4
+      stage: vim8
 install: |
   git config --global user.email "you@example.com"
   git config --global user.name "Your Name"

test/run

@@ -127,9 +127,11 @@ git --version
 vim=$(select_vim)
 echo "Selected Vim: $vim"
 if [ "${1:-}" = '!' ]; then
-  $vim -Nu $TEMP/mini-vimrc -c 'Vader! test.vader' > /dev/null &&
-  prepare &&
-  $vim -Nu $TEMP/mini-vimrc -c 'let g:plug_threads = 1 | Vader! test.vader' > /dev/null
+  FAIL=0
+  $vim -Nu $TEMP/mini-vimrc -c 'Vader! test.vader' > /dev/null || FAIL=1
+  prepare
+  $vim -Nu $TEMP/mini-vimrc -c 'let g:plug_threads = 1 | Vader! test.vader' > /dev/null || FAIL=1
+  test $FAIL -eq 0
 else
   $vim -Nu $TEMP/mini-vimrc -c 'Vader test.vader'
 fi

test/workflow.vader

@@ -50,7 +50,7 @@ Execute (Test Plug command):
 
 ^ Git repo with tag (DEPRECATED. USE TAG OPTION)
   redir => out
-  Plug 'foo/bar.vim', ''
+  silent Plug 'foo/bar.vim', ''
   redir END
   Assert out =~ 'Invalid argument for "tag" option of :Plug (expected: string)'
   Plug 'junegunn/goyo.vim', '1.5.2'
@@ -59,7 +59,7 @@ Execute (Test Plug command):
   AssertEqual '1.5.2', g:plugs['goyo.vim'].tag
 
   redir => out
-  Plug 'foo/bar.vim', {'tag': ''}
+  silent Plug 'foo/bar.vim', {'tag': ''}
   redir END
   Assert out =~ 'Invalid argument for "tag" option of :Plug (expected: string)'
   Plug 'junegunn/goyo.vim', { 'tag': '1.5.3' } " Using tag option
@@ -86,19 +86,23 @@ Execute (Test Plug command):
 Execute (Plug command with dictionary option):
   Log string(g:plugs)
   for opt in ['branch', 'tag', 'commit', 'rtp', 'dir', 'as']
+    let opts = {}
+    let opts[opt] = ''
     redir => out
-    Plug 'foo/bar.vim', {opt: ''}
+    silent Plug 'foo/bar.vim', opts
     redir END
     Assert out =~ 'Invalid argument for "'.opt.'" option of :Plug (expected: string)'
   endfor
   for opt in ['on', 'for']
+    let opts = {}
+    let opts[opt] = ''
     redir => out
-    Plug 'foo/bar.vim', {opt: ''}
+    silent Plug 'foo/bar.vim', opts
     redir END
     Assert out =~ 'Invalid argument for "'.opt.'" option of :Plug (expected: string or list)'
   endfor
   redir => out
-  Plug 'foo/bar.vim', {'do': ''}
+  silent Plug 'foo/bar.vim', {'do': ''}
   redir END
   Assert out =~ 'Invalid argument for "do" option of :Plug (expected: string or funcref)'
   Plug 'junegunn/seoul256.vim', { 'branch': 'no-t_co', 'rtp': '././' }