Add CLI file feature

CHANGES.md

@@ -58,6 +58,8 @@ https://github.com/nimterop/nimterop/compare/v0.4.4...v0.5.0
 
 - `toast` also includes `--typeMap | -T` to map C types to another type. E.g. `--typeMap:GLint64=int64` generates a wrapper where all instances of `GLint64` are remapped to the Nim type `int64` and `GLint64` is not defined. (since v0.5.2)
 
+- CLI flags can now be specified one or more per line in a file and path provided to `toast`. They will be expanded in place. [#196][i196] (since v0.5.3)
+
 - Nimterop is now able to detect Nim configuration of projects and can better handle cases where defaults such as `nimcacheDir` or `nimblePath` are overridden. This especially enables better interop with workflows that do not depend on Nimble. [#151][i151] [#153][i153]
 
 - Nimterop defaults to `cmake`, followed by `autoconf` for building libraries with `getHeader()`. It is now possible to change the order of discovery with the `buildType` value. [#200][i200]
@@ -78,5 +80,6 @@ https://github.com/nimterop/nimterop/compare/v0.4.4...v0.5.0
 [i174]: https://github.com/nimterop/nimterop/issues/174
 [i176]: https://github.com/nimterop/nimterop/issues/176
 [i181]: https://github.com/nimterop/nimterop/issues/181
+[i196]: https://github.com/nimterop/nimterop/issues/196
 [i197]: https://github.com/nimterop/nimterop/issues/197
 [i200]: https://github.com/nimterop/nimterop/issues/200

README.md

@@ -195,14 +195,14 @@ Nimterop also provides a [docs](https://nimterop.github.io/nimterop/docs.html) A
 
 ### Command line API
 
-The `toast` binary can also be used directly on the CLI, similar to `c2nim`. The `cPlugin()` interface
+The `toast` binary can also be used directly on the CLI, similar to `c2nim`. These flags can be specified on the command line or via a file, one or more flags per line, and the path provided to `toast` instead, or a combination. The file contents will be expanded in place.
 
 Note: unlike the wrapper API, the `-p | --preprocess` flag is not enabled by default but is *highly* recommended.
 
 ```
 > toast -h
 Usage:
-  main [optional-params] C/C++ source/header
+  main [optional-params] C/C++ source/header(s) and command line file(s)
 Options:
   -h, --help                              print this cligen-erated help
   --help-syntax                           advanced: prepend,plurals,..

nimterop.nimble

@@ -59,8 +59,8 @@ task test, "Test":
   execTest "tests/tnimterop_c.nim", "-d:FLAGS=\"-f:ast2 -H\""
 
   execCmd "nim cpp --hints:off -f -r tests/tnimterop_cpp.nim"
-  execCmd "./nimterop/toast -pnk -E=_ tests/include/toast.h"
-  execCmd "./nimterop/toast -pnk -E=_ -f:ast2 tests/include/toast.h"
+  execCmd "./nimterop/toast tests/toast.cfg tests/include/toast.h"
+  execCmd "./nimterop/toast tests/toast.cfg -f:ast2 tests/include/toast.h"
 
   execTest "tests/tpcre.nim"
   execTest "tests/tpcre.nim", "-d:FLAGS=\"-f:ast2\""

nimterop/ast2.nim

@@ -139,7 +139,7 @@ proc newConstDef(gState: State, node: TSNode, fname = "", fval = ""): PNode =
     else:
       gecho &"# const '{origname}' is duplicate, skipped"
   else:
-    gecho &"# const '{origname}' has invalid value '{val}'"
+    gecho &"# const '{origname}' has unsupported value '{val}'"
     gState.skippedSyms.incl origname
 
 proc addConst(gState: State, node: TSNode) =
@@ -1736,19 +1736,9 @@ proc setupPragmas(gState: State, root: TSNode, fullpath: string) =
   # Add `{.experimental: "codeReordering".} for #206
   gState.pragmaSection.add gState.newPragma(root, "experimental", newStrNode(nkStrLit, "codeReordering"))
 
-proc printNimHeader*(gState: State) =
-  # Top level output with context info
-  gecho """# Generated at $1
-# Command line:
-#   $2 $3
-
-{.hint[ConvFromXtoItselfNotNeeded]: off.}
-
-import nimterop/types
-""" % [$now(), getAppFilename(), commandLineParams().join(" ")]
-
 proc initNim*(gState: State) =
   # Initialize for parseNim() one time
+  gecho "import nimterop/types\n"
 
   # Track identifiers already rendered and corresponding PNodes
   gState.identifiers = newTable[string, string]()

nimterop/toast.nim

@@ -141,7 +141,6 @@ proc main(
   elif source.nBl:
     # Print source after preprocess or Nim output
     if gState.pnim:
-      gState.printNimHeader()
       gState.initNim()
     for src in source:
       gState.process(src.expandSymlinkAbs(), astTable)
@@ -199,6 +198,29 @@ proc main(
   if check and output.len == 0:
     stdout.write outputFile.readFile()
 
+proc mergeParams(cmdNames: seq[string], cmdLine = commandLineParams()): seq[string] =
+  # Load command-line params from `source` if it is a .cfg file
+  if cmdNames.len != 0:
+    # https://github.com/c-blake/cligen/issues/149
+    for param in cmdLine:
+      if param.fileExists() and param.splitFile().ext == ".cfg":
+        echo &"# Loading flags from '{param}'"
+        for line in param.readFile().splitLines():
+          let
+            line = line.strip()
+          if line.len > 1 and line[0] != '#':
+            result.add line.parseCmdLine()
+      else:
+        result.add param
+
+    if result.len != 0 and "-h" notin result and "--help" notin result:
+      echo &"""# Generated @ {$now()}
+# Command line:
+#   {getAppFilename()} {result.join(" ")}
+"""
+  else:
+    result = cmdLine
+
 when isMainModule:
   # Setup cligen command line help and short flags
   import cligen
@@ -223,7 +245,7 @@ when isMainModule:
     "preprocess": "run preprocessor on header",
     "recurse": "process #include files",
     "replace": "replace X with Y in identifiers, X1=Y1,X2=Y2, @X for regex",
-    "source" : "C/C++ source/header",
+    "source" : "C/C++ source/header(s) and command line file(s)",
     "stub": "stub out undefined type references as objects",
     "suffix": "strip suffix from identifiers",
     "symOverride": "skip generating specified symbols",

tests/toast.cfg

@@ -0,0 +1,2 @@
+--preprocess
+-nk -E=_