Version to test

README.md

@@ -122,6 +122,7 @@ An example for a Configuration file is given below
   "incremental_sync": true,
   "lowercase_intrinsics": true,
   "hover_signature": true,
+  "folding_range": true,
   "use_signature_help": true,
   "excl_paths": ["tests/**", "tools/**"],
   "excl_suffixes": ["_skip.f90"],

docs/options.rst

@@ -66,6 +66,8 @@ All the ``fortls`` settings with their default arguments can be found below
       "hover_signature": false,
       "hover_language": "fortran90",
 
+      "folding_range": false
+
       "max_line_length": -1,
       "max_comment_line_length": -1,
       "disable_diagnostics": false,

fortls/fortls.schema.json

@@ -135,6 +135,12 @@
       "title": "Hover Language",
       "type": "string"
     },
+    "folding_range": {
+      "default": false,
+      "description": "Fold editor based on language keywords",
+      "title": "Folding Range",
+      "type": "boolean"
+    },
     "max_line_length": {
       "default": -1,
       "description": "Maximum line length (default: -1)",

fortls/interface.py

@@ -210,6 +210,13 @@ def cli(name: str = "fortls") -> argparse.ArgumentParser:
         ),
     )
 
+    # Folding range ------------------------------------------------------------
+    group.add_argument(
+        "--folding_range",
+        action="store_true",
+        help="Fold editor based on language keywords",
+    )
+
     # Diagnostic options -------------------------------------------------------
     group = parser.add_argument_group("Diagnostic options (error swigles)")
     group.add_argument(

fortls/langserver.py

@@ -146,6 +146,7 @@ def noop(request: dict):
             "textDocument/hover": self.serve_hover,
             "textDocument/implementation": self.serve_implementation,
             "textDocument/rename": self.serve_rename,
+            "textDocument/foldingRange": self.serve_folding_range,
             "textDocument/didOpen": self.serve_onOpen,
             "textDocument/didSave": self.serve_onSave,
             "textDocument/didClose": self.serve_onClose,
@@ -226,6 +227,7 @@ def serve_initialize(self, request: dict):
             "renameProvider": True,
             "workspaceSymbolProvider": True,
             "textDocumentSync": self.sync_type,
+            "foldingRangeProvider": True,
         }
         if self.use_signature_help:
             server_capabilities["signatureHelpProvider"] = {
@@ -1224,6 +1226,56 @@ def serve_rename(self, request: dict):
                 )
         return {"changes": changes}
 
+    def serve_folding_range(self, request: dict):
+        # Get parameters from request
+        params: dict = request["params"]
+        uri: str = params["textDocument"]["uri"]
+        path = path_from_uri(uri)
+        # Find object
+        file_obj = self.workspace.get(path)
+        if file_obj is None:
+            return None
+        if file_obj.ast is None:
+            return None
+        else:
+            folding_start = file_obj.ast.folding_start
+            folding_end = file_obj.ast.folding_end
+        if (
+            folding_start is None
+            or folding_end is None
+            or len(folding_start) != len(folding_end)
+        ):
+            return None
+        # Construct folding_rage list
+        folding_ranges = []
+        # First treating scope objects...
+        for scope in file_obj.ast.scope_list:
+            n_mlines = len(scope.mlines)
+            # ...with intermediate folding lines (if, select)...
+            if n_mlines > 0:
+                self.add_range(folding_ranges, scope.sline - 1, scope.mlines[0] - 2)
+                for i in range(1, n_mlines):
+                    self.add_range(
+                        folding_ranges, scope.mlines[i - 1] - 1, scope.mlines[i] - 2
+                    )
+                self.add_range(folding_ranges, scope.mlines[-1] - 1, scope.eline - 2)
+            # ...and without
+            else:
+                self.add_range(folding_ranges, scope.sline - 1, scope.eline - 2)
+        # Then treat comment blocks
+        folds = len(folding_start)
+        for i in range(0, folds):
+            self.add_range(folding_ranges, folding_start[i] - 1, folding_end[i] - 1)
+
+        return folding_ranges
+
+    def add_range(self, folding_ranges: list, start: int, end: int):
+        folding_range = {
+            "startLine": start,
+            "endLine": end,
+        }
+        folding_ranges.append(folding_range)
+
     def serve_codeActions(self, request: dict):
         params: dict = request["params"]
         uri: str = params["textDocument"]["uri"]
@@ -1621,6 +1673,9 @@ def _load_config_file_general(self, config_dict: dict) -> None:
         self.hover_signature = config_dict.get("hover_signature", self.hover_signature)
         self.hover_language = config_dict.get("hover_language", self.hover_language)
 
+        # Folding range --------------------------------------------------------
+        self.folding_range = config_dict.get("folding_range", self.folding_range)
+
         # Diagnostic options ---------------------------------------------------
         self.max_line_length = config_dict.get("max_line_length", self.max_line_length)
         self.max_comment_line_length = config_dict.get(

fortls/parsers/internal/ast.py

@@ -34,6 +34,10 @@ def __init__(self, file_obj=None):
         self.inherit_objs: list = []
         self.linkable_objs: list = []
         self.external_objs: list = []
+        self.folding_start: list = []
+        self.folding_end: list = []
+        self.comment_block_start = 0
+        self.comment_block_end = 0
         self.none_scope = None
         self.inc_scope = None
         self.current_scope = None