Add sections (type, var, let, const, using) support for reorder pragma (#6326)

compiler/modulepaths.nim

@@ -0,0 +1,78 @@
+#
+#    See the file "copying.txt", included in this
+#    distribution, for details about the copyright.
+#
+
+import ast, renderer, gorgeimpl, strutils, msgs, options, idents, ospaths
+
+proc lookupPackage(pkg, subdir: PNode): string =
+  let sub = if subdir != nil: renderTree(subdir, {renderNoComments}).replace(" ") else: ""
+  case pkg.kind
+  of nkStrLit, nkRStrLit, nkTripleStrLit:
+    result = scriptableImport(pkg.strVal, sub, pkg.info)
+  of nkIdent:
+    result = scriptableImport(pkg.ident.s, sub, pkg.info)
+  else:
+    localError(pkg.info, "package name must be an identifier or string literal")
+    result = ""
+
+proc getModuleName*(n: PNode): string =
+  # This returns a short relative module name without the nim extension
+  # e.g. like "system", "importer" or "somepath/module"
+  # The proc won't perform any checks that the path is actually valid
+  case n.kind
+  of nkStrLit, nkRStrLit, nkTripleStrLit:
+    try:
+      result = pathSubs(n.strVal, n.info.toFullPath().splitFile().dir)
+    except ValueError:
+      localError(n.info, "invalid path: " & n.strVal)
+      result = n.strVal
+  of nkIdent:
+    result = n.ident.s
+  of nkSym:
+    result = n.sym.name.s
+  of nkInfix:
+    let n0 = n[0]
+    let n1 = n[1]
+    if n0.kind == nkIdent and n0.ident.id == getIdent("as").id:
+      # XXX hack ahead:
+      n.kind = nkImportAs
+      n.sons[0] = n.sons[1]
+      n.sons[1] = n.sons[2]
+      n.sons.setLen(2)
+      return getModuleName(n.sons[0])
+    if n1.kind == nkPrefix and n1[0].kind == nkIdent and n1[0].ident.s == "$":
+      if n0.kind == nkIdent and n0.ident.s == "/":
+        result = lookupPackage(n1[1], n[2])
+      else:
+        localError(n.info, "only '/' supported with $package notation")
+        result = ""
+    else:
+      # hacky way to implement 'x / y /../ z':
+      result = getModuleName(n1)
+      result.add renderTree(n0, {renderNoComments})
+      result.add getModuleName(n[2])
+  of nkPrefix:
+    if n.sons[0].kind == nkIdent and n.sons[0].ident.s == "$":
+      result = lookupPackage(n[1], nil)
+    else:
+      # hacky way to implement 'x / y /../ z':
+      result = renderTree(n, {renderNoComments}).replace(" ")
+  of nkDotExpr:
+    result = renderTree(n, {renderNoComments}).replace(".", "/")
+  of nkImportAs:
+    result = getModuleName(n.sons[0])
+  else:
+    localError(n.info, errGenerated, "invalid module name: '$1'" % n.renderTree)
+    result = ""
+
+proc checkModuleName*(n: PNode; doLocalError=true): int32 =
+  # This returns the full canonical path for a given module import
+  let modulename = n.getModuleName
+  let fullPath = findModule(modulename, n.info.toFullPath)
+  if fullPath.len == 0:
+    if doLocalError:
+      localError(n.info, errCannotOpenFile, modulename)
+    result = InvalidFileIDX
+  else:
+    result = fullPath.fileInfoIdx