Fix #315 Implement the read_buffer option

6 files changed, 262 insertions, 29 deletions

diff --git a/autoload/ale/engine.vim b/autoload/ale/engine.vim
index 34e5ad95..59c6de77 100644
--- a/autoload/ale/engine.vim
+++ b/autoload/ale/engine.vim
@@ -214,13 +214,13 @@ function! s:FixLocList(buffer, loclist) abort
     endfor
 endfunction
 
-function! s:RunJob(command, generic_job_options) abort
-    let l:buffer = a:generic_job_options.buffer
-    let l:linter = a:generic_job_options.linter
-    let l:output_stream = a:generic_job_options.output_stream
-    let l:next_chain_index = a:generic_job_options.next_chain_index
-    let l:read_buffer = a:generic_job_options.read_buffer
-    let l:command = a:command
+function! s:RunJob(options) abort
+    let l:command = a:options.command
+    let l:buffer = a:options.buffer
+    let l:linter = a:options.linter
+    let l:output_stream = a:options.output_stream
+    let l:next_chain_index = a:options.next_chain_index
+    let l:read_buffer = a:options.read_buffer
 
     if l:command =~# '%s'
         " If there is a '%s' in the command string, replace it with the name
@@ -321,8 +321,11 @@ function! s:RunJob(command, generic_job_options) abort
     endif
 endfunction
 
-function! s:InvokeChain(buffer, linter, chain_index, input) abort
+" Determine which commands to run for a link in a command chain, or
+" just a regular command.
+function! ale#engine#ProcessChain(buffer, linter, chain_index, input) abort
     let l:output_stream = get(a:linter, 'output_stream', 'stdout')
+    let l:read_buffer = a:linter.read_buffer
     let l:chain_index = a:chain_index
     let l:input = a:input
 
@@ -332,11 +335,6 @@ function! s:InvokeChain(buffer, linter, chain_index, input) abort
             " so that many programs can be run in a sequence.
             let l:chain_item = a:linter.command_chain[l:chain_index]
 
-            " The chain item can override the output_stream option.
-            if has_key(l:chain_item, 'output_stream')
-                let l:output_stream = l:chain_item.output_stream
-            endif
-
             if l:chain_index == 0
                 " The first callback in the chain takes only a buffer number.
                 let l:command = ale#util#GetFunction(l:chain_item.callback)(
@@ -352,6 +350,21 @@ function! s:InvokeChain(buffer, linter, chain_index, input) abort
 
             if !empty(l:command)
                 " We hit a command to run, so we'll execute that
+
+                " The chain item can override the output_stream option.
+                if has_key(l:chain_item, 'output_stream')
+                    let l:output_stream = l:chain_item.output_stream
+                endif
+
+                " The chain item can override the read_buffer option.
+                if has_key(l:chain_item, 'read_buffer')
+                    let l:read_buffer = l:chain_item.read_buffer
+                elseif l:chain_index != len(a:linter.command_chain) - 1
+                    " Don't read the buffer for commands besides the last one
+                    " in the chain by default.
+                    let l:read_buffer = 0
+                endif
+
                 break
             endif
 
@@ -361,11 +374,6 @@ function! s:InvokeChain(buffer, linter, chain_index, input) abort
             let l:input = []
             let l:chain_index += 1
         endwhile
-
-        if empty(l:command)
-            " Don't run any jobs if the last command is an empty string.
-            return
-        endif
     elseif has_key(a:linter, 'command_callback')
         " If there is a callback for generating a command, call that instead.
         let l:command = ale#util#GetFunction(a:linter.command_callback)(a:buffer)
@@ -373,15 +381,27 @@ function! s:InvokeChain(buffer, linter, chain_index, input) abort
         let l:command = a:linter.command
     endif
 
-    let l:is_last_job = l:chain_index >= len(get(a:linter, 'command_chain', [])) - 1
+    if empty(l:command)
+        " Don't run any jobs if the command is an empty string.
+        return {}
+    endif
 
-    call s:RunJob(l:command, {
+    return {
+    \   'command': l:command,
     \   'buffer': a:buffer,
     \   'linter': a:linter,
     \   'output_stream': l:output_stream,
     \   'next_chain_index': l:chain_index + 1,
-    \   'read_buffer': l:is_last_job,
-    \})
+    \   'read_buffer': l:read_buffer,
+    \}
+endfunction
+
+function! s:InvokeChain(buffer, linter, chain_index, input) abort
+    let l:options = ale#engine#ProcessChain(a:buffer, a:linter, a:chain_index, a:input)
+
+    if !empty(l:options)
+        call s:RunJob(l:options)
+    endif
 endfunction
 
 function! ale#engine#Invoke(buffer, linter) abort
diff --git a/autoload/ale/linter.vim b/autoload/ale/linter.vim
index be173588..260c145b 100644
--- a/autoload/ale/linter.vim
+++ b/autoload/ale/linter.vim
@@ -33,6 +33,10 @@ function! s:IsCallback(value) abort
     return type(a:value) == type('') || type(a:value) == type(function('type'))
 endfunction
 
+function! s:IsBoolean(value) abort
+    return type(a:value) == type(0) && (a:value == 0 || a:value == 1)
+endfunction
+
 function! ale#linter#PreProcess(linter) abort
     if type(a:linter) != type({})
         throw 'The linter object must be a Dictionary'
@@ -95,6 +99,10 @@ function! ale#linter#PreProcess(linter) abort
                 endif
             endif
 
+            if has_key(l:link, 'read_buffer') && !s:IsBoolean(l:link.read_buffer)
+                throw l:err_prefix . 'value for `read_buffer` must be `0` or `1`'
+            endif
+
             let l:link_index += 1
         endfor
     elseif has_key(a:linter, 'command_callback')
@@ -130,6 +138,13 @@ function! ale#linter#PreProcess(linter) abort
         throw "`output_stream` must be 'stdout', 'stderr', or 'both'"
     endif
 
+    " An option indicating that the buffer should be read.
+    let l:obj.read_buffer = get(a:linter, 'read_buffer', 1)
+
+    if !s:IsBoolean(l:obj.read_buffer)
+        throw '`read_buffer` must be `0` or `1`'
+    endif
+
     return l:obj
 endfunction
 
diff --git a/doc/ale.txt b/doc/ale.txt
index 348be809..a4d476c3 100644
--- a/doc/ale.txt
+++ b/doc/ale.txt
@@ -1082,10 +1082,14 @@ ale#linter#Define(filetype, linter)                       *ale#linter#Define()*
                          See the `output_stream` description for more
                          information.
 
-                         The Vim buffer being checked for linter will only
-                         be sent to the final command in the chain. Previous
-                         commands in the chain will receive no input from
-                         stdin.
+                         Commands in the chain all behave as if `read_buffer`
+                         is set to `0` by default, except for the last command
+                         in the chain, which uses the value set for
+                         `read_buffer` in the root |Dictionary|. Each command
+                         in the chain can also provide a `read_buffer` key
+                         to override these values.
+                         See the `read_buffer` description for more
+                         information.
 
   `output_stream`          A |String| for the output stream the lines of output
                          should be read from for the command which is run. The
@@ -1096,6 +1100,12 @@ ale#linter#Define(filetype, linter)                       *ale#linter#Define()*
                          instead of stdout. The option `'both'` will read
                          from both stder and stdout at the same time.
 
+  `read_buffer`            A |Number| (`0` or `1`) indicating whether a command
+                         should read the Vim buffer as input via stdin. This
+                         option is set to `1` by default, and can be disabled
+                         if a command manually reads from a temporary file
+                         instead, etc.
+
   Only one of `command`, `command_callback`, or `command_chain` should be
   specified. `command_callback` is generally recommended when a command string
   needs to be generated dynamically, or any global options are used.
diff --git a/test/test_engine_invocation.vader b/test/test_engine_invocation.vader
new file mode 100644
index 00000000..c56895d3
--- /dev/null
+++ b/test/test_engine_invocation.vader
@@ -0,0 +1,139 @@
+Before:
+  function! CollectResults(buffer, output)
+    return []
+  endfunction
+
+  function! FirstChainFunction(buffer)
+    return 'first'
+  endfunction
+
+  function! SecondChainFunction(buffer, output)
+    " We'll skip this command
+    return ''
+  endfunction
+
+  function! ThirdChainFunction(buffer, output)
+    return 'third'
+  endfunction
+
+  function! FourthChainFunction(buffer, output)
+    return 'fourth'
+  endfunction
+
+  let g:linter = {
+  \ 'name': 'testlinter',
+  \ 'callback': 'CollectResults',
+  \ 'executable': 'echo',
+  \ 'command_chain': [
+  \   {'callback': 'FirstChainFunction'},
+  \   {'callback': 'SecondChainFunction'},
+  \   {'callback': 'ThirdChainFunction'},
+  \   {'callback': 'FourthChainFunction'},
+  \ ],
+  \ 'read_buffer': 1,
+  \}
+
+  function! ProcessIndex(chain_index)
+    return ale#engine#ProcessChain(347, g:linter, a:chain_index, [])
+  endfunction
+
+After:
+  delfunction CollectResults
+  delfunction FirstChainFunction
+  delfunction SecondChainFunction
+  delfunction ThirdChainFunction
+  delfunction ProcessIndex
+  unlet! g:linter
+  unlet! g:result
+
+Execute(Engine invocation should return the command for the first item correctly):
+  let g:result = ProcessIndex(0)
+
+  AssertEqual 'first', g:result.command
+  AssertEqual 1, g:result.next_chain_index
+
+Execute(Engine invocation should return the command for the second item correctly):
+  let g:result = ProcessIndex(1)
+
+  AssertEqual 'third', g:result.command
+  AssertEqual 3, g:result.next_chain_index
+
+Execute(Engine invocation should return the command for the fourth item correctly):
+  let g:result = ProcessIndex(3)
+
+  AssertEqual 'fourth', g:result.command
+  AssertEqual 4, g:result.next_chain_index
+
+Execute(Engine invocation should return the command for a single callback correctly):
+  unlet g:linter.command_chain
+  let g:linter.command_callback = 'FirstChainFunction'
+
+  let g:result = ProcessIndex(0)
+
+  AssertEqual 'first', g:result.command
+
+Execute(Engine invocation should return the command for a command string correctly):
+  unlet g:linter.command_chain
+  let g:linter.command = 'foo bar'
+
+  let g:result = ProcessIndex(0)
+
+  AssertEqual 'foo bar', g:result.command
+
+Execute(Engine invocation should process read_buffer correctly for simple commands):
+  unlet g:linter.command_chain
+  let g:linter.command = 'foo bar'
+  let g:linter.read_buffer = 0
+
+  let g:result = ProcessIndex(0)
+
+  AssertEqual 'foo bar', g:result.command
+  AssertEqual 0, g:result.read_buffer
+
+  let g:linter.command_callback = 'FirstChainFunction'
+  unlet g:linter.command
+
+  let g:result = ProcessIndex(0)
+
+  AssertEqual 'first', g:result.command
+  AssertEqual 0, g:result.read_buffer
+
+Execute(Engine invocation should allow read_buffer to be enabled for a command in the middle of a chain):
+  let g:linter.command_chain[2].read_buffer = 1
+
+  let g:result = ProcessIndex(2)
+
+  AssertEqual g:result.command, 'third'
+  AssertEqual g:result.read_buffer, 1
+
+Execute(Engine invocation should allow read_buffer to be disabled for the end of a chain):
+  let g:linter.command_chain[3].read_buffer = 0
+
+  let g:result = ProcessIndex(3)
+
+  AssertEqual g:result.command, 'fourth'
+  AssertEqual g:result.read_buffer, 0
+
+Execute(Engine invocation should not use read_buffer from earlier items in a chain):
+  let g:linter.command_chain[1].read_buffer = 1
+
+  let g:result = ProcessIndex(1)
+
+  AssertEqual g:result.command, 'third'
+  AssertEqual g:result.read_buffer, 0
+
+Execute(Engine invocation should allow the output_stream setting to be changed in the middle of a chain):
+  let g:linter.command_chain[2].output_stream = 'both'
+
+  let g:result = ProcessIndex(2)
+
+  AssertEqual g:result.command, 'third'
+  AssertEqual g:result.output_stream, 'both'
+
+Execute(Engine invocation should not use output_stream from earlier items in a chain):
+  let g:linter.command_chain[1].output_stream = 'both'
+
+  let g:result = ProcessIndex(1)
+
+  AssertEqual g:result.command, 'third'
+  AssertEqual g:result.output_stream, 'stdout'
diff --git a/test/test_linter_defintion_processing.vader b/test/test_linter_defintion_processing.vader
index 969a8932..3acc194e 100644
--- a/test/test_linter_defintion_processing.vader
+++ b/test/test_linter_defintion_processing.vader
@@ -234,3 +234,52 @@ Execute(PreProcess should complain when conflicting command options are used):
 
   AssertThrows call ale#linter#PreProcess(g:linter)
   AssertEqual 'Only one of `command`, `command_callback`, or `command_chain` should be set', g:vader_exception
+
+Execute(PreProcess should process the read_buffer option correctly):
+  let g:linter = {
+  \ 'name': 'x',
+  \ 'callback': 'x',
+  \ 'executable': 'x',
+  \ 'command_chain': [{'callback': 'foo'}, {'callback': 'bar'}],
+  \ 'read_buffer': '0',
+  \}
+
+  AssertThrows call ale#linter#PreProcess(g:linter)
+  AssertEqual '`read_buffer` must be `0` or `1`', g:vader_exception
+
+  let g:linter.read_buffer = 0
+
+  call ale#linter#PreProcess(g:linter)
+
+  let g:linter.read_buffer = 1
+
+  call ale#linter#PreProcess(g:linter)
+
+  unlet g:linter.read_buffer
+  let g:linter.command_chain[0].read_buffer = '0'
+
+  AssertThrows call ale#linter#PreProcess(g:linter)
+  AssertEqual 'The `command_chain` item 0 value for `read_buffer` must be `0` or `1`', g:vader_exception
+
+  let g:linter.command_chain[0].read_buffer = 0
+
+  call ale#linter#PreProcess(g:linter)
+
+  let g:linter.command_chain[1].read_buffer = '0'
+
+  AssertThrows call ale#linter#PreProcess(g:linter)
+  AssertEqual 'The `command_chain` item 1 value for `read_buffer` must be `0` or `1`', g:vader_exception
+
+  let g:linter.command_chain[1].read_buffer = 1
+
+  call ale#linter#PreProcess(g:linter)
+
+Execute(PreProcess should set a default value for read_buffer):
+  let g:linter = {
+  \ 'name': 'x',
+  \ 'callback': 'x',
+  \ 'executable': 'x',
+  \ 'command': 'x',
+  \}
+
+  AssertEqual ale#linter#PreProcess(g:linter).read_buffer, 1
diff --git a/test/test_linter_retrieval.vader b/test/test_linter_retrieval.vader
index 5dadf6bc..bc5b62ef 100644
--- a/test/test_linter_retrieval.vader
+++ b/test/test_linter_retrieval.vader
@@ -1,6 +1,6 @@
 Before:
-  let g:testlinter1 = {'name': 'testlinter1', 'executable': 'testlinter1', 'command': 'testlinter1', 'callback': 'testCB1', 'output_stream': 'stdout'}
-  let g:testlinter2 = {'name': 'testlinter2', 'executable': 'testlinter2', 'command': 'testlinter2', 'callback': 'testCB2', 'output_stream': 'stdout'}
+  let g:testlinter1 = {'name': 'testlinter1', 'executable': 'testlinter1', 'command': 'testlinter1', 'callback': 'testCB1', 'output_stream': 'stdout', 'read_buffer': 1}
+  let g:testlinter2 = {'name': 'testlinter2', 'executable': 'testlinter2', 'command': 'testlinter2', 'callback': 'testCB2', 'output_stream': 'stdout', 'read_buffer': 0}
 
   call ale#linter#Reset()
   let g:ale_linters = {}
@@ -40,4 +40,4 @@ Then (Linters for dot-seperated filetypes should be properly handled):
   AssertEqual [g:testlinter1, g:testlinter2], ale#linter#Get('testft1.testft2')
 
 Execute (Try to load a linter from disk):
-  AssertEqual [{'name': 'testlinter', 'output_stream': 'stdout', 'executable': 'testlinter', 'command': 'testlinter', 'callback': 'testCB'}], ale#linter#Get('testft')
+  AssertEqual [{'name': 'testlinter', 'output_stream': 'stdout', 'executable': 'testlinter', 'command': 'testlinter', 'callback': 'testCB', 'read_buffer': 1}], ale#linter#Get('testft')