fortls - Fortran Language Server

fortls is an implementation of the Language Server Protocol (LSP) for Fortran using Python (3.7+).

All code editors that support LSP can integrate with fortls see the section Editor Integration in the documentation. Some supported code editors include: Visual Studio Code, Atom, Sublime Text, (Neo)Vim, and Emacs.

Features

Project-wide and Document symbol detection and Renaming
Hover support, Signature help and Auto-completion
GoTo/Peek implementation and Find/Peek references
Preprocessor support
Documentation parsing (Doxygen and FORD styles)
Access to multiple intrinsic modules and functions
- ISO_FORTRAN_ENV GCC 11.2.0
- IOS_C_BINDING GCC 11.2.0
- IEEE_EXCEPTIONS, IEEE_ARITHMETIC, IEEE_FEATURES GCC 11.2.0
- OpenMP OMP_LIB, OMP_LIB_KINDS v5.0
- OpenACC OPENACC, OPENACC_KINDS v3.1
Diagnostics
- Multiple definitions with the same variable name
- Variable definition masks definition from parent scope
- Missing subroutine/function arguments
- Unknown user-defined type used in TYPE/CLASS definition (only if visible in project)
- Unclosed blocks/scopes
- Invalid scope nesting
- Unknown modules in USE statement
- Unimplemented deferred type-bound procedures
- Use of non-imported variables/objects in interface blocks
- Statement placement errors (CONTAINS, IMPLICIT, IMPORT)
Code actions
- Generate type-bound procedures and implementation templates for deferred procedures

Notes/Limitations

Signature help and hover does not handle elegantly overloaded functions i.e. interfaces

`fortls` vs `fortran-language-server`

This project was originally based on fortran-language-server LSP implementation, but the two projects have since diverged.

fortls (this project) is now developed independently of the upstream hansec/fortran-language-server project and contains numerous new features and bug fixes the original fortran-language-server does not.

For a complete and detailed list of the differences between the two Language Servers see the Documentation section: Unique fortls features (not in fortran-language-server)

The name of executable for this project has been chosen to remain fortls to allow for integration with pre-existing plugins and workflows, but it could change in the future.

Installation

PyPi

pip install fortls

Anaconda

conda install -c conda-forge fortls

for more information about the Anaconda installation see

Common installation problems

It is NOT recommended having fortls and fortran-language-server simultaneously installed, since they use the same binary name. If you are having trouble getting fortls to work try uninstalling fortran-language-server and reinstalling fortls.

With pip

pip uninstall fortran-language-server
pip install fortls --upgrade

or with Anaconda

conda uninstall fortran-language-server
conda install -c conda-forge fortls

Settings

fortls can be configured through both the command line e.g. fortls --hover_signature or through a Configuration json file. The two interfaces are identical and a full list of the available options can be found in the Documentation or through fortls -h

An example for a Configuration file is given below

{
  "incremental_sync": true,
  "lowercase_intrinsics": true,
  "hover_signature": true,
  "use_signature_help": true,
  "excl_paths": ["tests/**", "tools/**"],
  "excl_suffixes": ["_skip.f90"],
  "include_dirs": ["include/**"],
  "pp_suffixes": [".F90", ".h"],
  "pp_defs": { "HAVE_HDF5": "", "MPI_Comm": "integer" }
}

Implemented server requests

Request	Description
`workspace/symbol`	Get workspace-wide symbols
`textDocument/documentSymbol`	Get document symbols e.g. functions, subroutines, etc.
`textDocument/completion`	Suggested tab-completion when typing
`textDocument/signatureHelp`	Get signature information at a given cursor position
`textDocument/definition`	GoTo definition/Peek definition
`textDocument/references`	Find all/Peek references
`textDocument/hover`	Show messages and signatures upon hover
`textDocument/implementation`	GoTo implementation/Peek implementation
`textDocument/rename`	Rename a symbol across the workspace
`textDocument/didOpen`	Document synchronisation upon opening
`textDocument/didSave`	Document synchronisation upon saving
`textDocument/didClose`	Document synchronisation upon closing
`textDocument/didChange`	Document synchronisation upon changes to the document
`textDocument/codeAction`	Experimental Generate code

Acknowledgements

This project would not have been possible without the original work of @hansec in fortran-language-server

Bug reports

When filing bugs please provide example code to reproduce the observed issue.

License

This project is made available under the MIT License.

nujabse/fortls