Added a nimble task to run nimpretty on all gitted files

nimfunge98.nimble

@@ -19,7 +19,25 @@ task test, "Runs the test suite":
 task coverage, "Run all tests and calculate coverage":
   exec "coco --target 'tests/**/*.nim' --cov '!tests,!nimcache'"
 
+import os, strformat
+
+task fmt, "Run nimpretty on all git-managed .nim files in the current repo":
+  ## Usage: nim fmt
+  for file in walkDirRec("./", {pcFile, pcDir}):
+    if file.splitFile().ext == ".nim":
+      let
+        # https://github.com/nim-lang/Nim/issues/6262#issuecomment-454983572
+        # https://stackoverflow.com/a/2406813/1219634
+        fileIsGitManaged = gorgeEx("cd $1 && git ls-files --error-unmatch $2" % [getCurrentDir(), file]).exitCode == 0
+        #                           ^^^^^-- That "cd" is required.
+      if fileIsGitManaged:
+        let
+          cmd = "nimpretty --maxLineLen=180 $1" % [file]
+        echo "Running $1 .." % [cmd]
+        exec(cmd)
+
 task clean, "Clean":
   exec "rm -rf coverage lcov.info nimcache"
   exec "rm -rf outputGotten.txt testresults tests/megatest.nim"
+  exec "rm -rf src/htmldocs"
   exec "find tests/ -type f -executable -delete"