Expands arc when hovering a proc (#275)

* expands arc when hovering a proc

* only expand arc in definitions

* Fixes an issue where nim processes accumulates and expands stop working. Adds clarification on hover

* Fixes an issue with expandMacro

nimcheck.nim

@@ -86,13 +86,18 @@ proc nimCheck*(filePath: string, nimPath: string): Future[seq[CheckResult]] {.as
     stderrHandle = AsyncProcess.Pipe,
     stdoutHandle = AsyncProcess.Pipe,
   )
-  let res = await process.waitForExit(InfiniteDuration)
-  # debug "nimCheck exit", res = res
-  var output = ""
-  if res == 0: #Nim check return 0 if there are no errors but we still need to check for hints and warnings
-    output = string.fromBytes(process.stdoutStream.read().await)   
-  else:
-    output = string.fromBytes(process.stderrStream.read().await)
+  try:
+    let res = await process.waitForExit(15.seconds)
+    # debug "nimCheck exit", res = res
+    var output = ""
+    if res == 0: #Nim check return 0 if there are no errors but we still need to check for hints and warnings
+      output = string.fromBytes(process.stdoutStream.read().await)   
+    else:
+      output = string.fromBytes(process.stderrStream.read().await)
 
-  let lines = output.splitLines()
-  parseCheckResults(lines)
+    let lines = output.splitLines()
+    parseCheckResults(lines)
+
+  finally:
+    if not process.isNil: 
+      discard process.kill()

nimexpand.nim

@@ -0,0 +1,86 @@
+import std/[strutils]
+import regex
+import chronos, chronos/asyncproc
+import stew/[byteutils]
+import chronicles
+import protocol/types
+import utils
+import suggestapi
+import std/[strscans, strformat]
+
+
+proc extractMacroExpansion*(output: string, targetLine: int): string =
+  var start = false
+  for line in output.split({'\n', '\r'}):
+    if line.len == 0: continue
+    debug "extractMacroExpansion", line = line, condMet = &".nim({targetLine}," in line
+    if &".nim({targetLine}," in line:
+      start = true
+    elif &".nim" in line and start:
+      break
+    if start:
+      result.add line & "\n"
+
+  if result.len > 0:
+    let macroStart = result.find("macro: ")
+    if macroStart != -1:
+      result = result.substr(macroStart + "macro: ".len)
+      result = result.replace("[ExpandMacro]", "")
+
+proc nimExpandMacro*(nimPath: string, suggest: Suggest, filePath: string): Future[string] {.async.} =
+  let 
+    macroName = suggest.qualifiedPath[suggest.qualifiedPath.len - 1]
+    line = suggest.line
+  debug "nimExpandMacro", macroName = macroName, line = line, filePath = filePath
+  debug "Executing ", cmd = &"nim c --expandMacro:{macroName} {filePath}"
+  let process = await startProcess(
+    nimPath,
+    arguments = @["c", "--expandMacro:" & macroName] & @[filePath],
+    options = {UsePath, StdErrToStdOut},
+    stdoutHandle = AsyncProcess.Pipe,
+  )
+  try:
+    let res = await process.waitForExit(10.seconds)
+    let output = string.fromBytes(process.stdoutStream.read().await)  
+    result = extractMacroExpansion(output, line)
+  finally:
+    if not process.isNil: 
+      discard process.kill()
+
+
+proc extractArcExpansion*(output: string, procName: string): string =
+  var start = false
+  let cond = &"--expandArc: {procName}"
+  for line in output.splitLines:
+    # debug "extractArcExpansion", line = line, condMet = cond in line
+    if cond in line:
+      start = true
+    elif &"-- end of expandArc" in line and start:
+      break
+    if start:
+      result.add line & "\n"
+
+  if result.len > 0:
+    result = result.replace(cond, "").strip()
+
+
+proc nimExpandArc*(nimPath: string, suggest: Suggest, filePath: string): Future[string] {.async.} =
+  let procName = suggest.qualifiedPath[suggest.qualifiedPath.len - 1]
+  debug "nimExpandArc", procName = procName, filePath = filePath
+  let process = await startProcess(
+    nimPath,
+    arguments = @["c", &"--expandArc:{procName}", "--compileOnly"] & @[filePath],
+    options = {UsePath, StdErrToStdOut},
+    stdoutHandle = AsyncProcess.Pipe,
+  )
+  try:
+    let res = await process.waitForExit(10.seconds)
+    let output = string.fromBytes(process.stdoutStream.read().await)  
+    result = extractArcExpansion(output, procName)
+    # debug "nimExpandArc", output = output, result = result
+    if result.len == 0:
+      result = &"#Couldnt expand arc for `{procName}`. Showing raw output instead (nimPath). \n"
+      result.add output      
+  finally:
+    if not process.isNil: 
+      discard process.kill()

routes.nim

@@ -19,8 +19,9 @@ import
   json_serialization,
   std/[strscans, times, json, parseutils, strutils],
   ls,
-  stew/[byteutils]
-
+  stew/[byteutils],
+  nimexpand,
+  nimcheck
 proc getNphPath(): Option[string] =
   let path = findExe "nph"
   if path == "":
@@ -402,8 +403,22 @@ proc hover*(
       if suggest.symkind == "skMacro":
         let expanded = await nimsuggest.get
           .expand(uriToPath(uri), ls.uriToStash(uri), suggest.line, suggest.column)
-        if expanded.len > 0:
+        if expanded.len > 0 and expanded[0].doc != "":
+          # debug "Expanded macro", expanded = expanded[0].doc
           content.add MarkedStringOption %* {"language": "nim", "value": expanded[0].doc}
+        else:          
+          # debug "Couldnt expand the macro. Trying with nim expand", suggest = suggest[]
+          let nimPath = ls.getWorkspaceConfiguration().await.getNimPath()
+          if nimPath.isSome:  
+            let expanded = await nimExpandMacro(nimPath.get, suggest, uriToPath(uri))
+            content.add MarkedStringOption %* {"language": "nim", "value": expanded}
+      if suggest.section == ideDef and suggest.symkind in ["skProc"]:
+        debug "#Expanding arc", suggest = suggest[]
+        let nimPath = ls.getWorkspaceConfiguration().await.getNimPath()
+        if nimPath.isSome:  
+          let expanded = await nimExpandArc(nimPath.get, suggest, uriToPath(uri))
+          let arcContent = "#Expanded arc \n" & expanded
+          content.add MarkedStringOption %* {"language": "nim", "value": arcContent}
       return some(Hover(
         contents: some(%content),
         range: some(toLabelRange(suggest.toUtf16Pos(ls))),