Project root not updated when editing file from different project

[cdelledonne]

Environment

• Plugin version: 3e31d01
• Plugin binary version: 0.1.146
• Neovim version: 0.3.5
• Language: C
• Language server: ccls latest release (0.20190314.1)

Describe the bug

After launching Neovim and editing a file belonging to a project in my workspace, LanguageClient successfully detects the project root, using my custom root marker. The project root is printed and logged correctly, and all the language client+server functionalities work. When I start editing another file belonging to a different project, the project root is not updated, in fact is remains the same as before thus breaking all the functionalities.

The workspace tree is something like the following:

workspace
│
├── project_a
│   ├── build
│   │   └── compile_commands.json
│   └── source
│       └── main.c
│
└── project_b
    ├── build
    │   └── compile_commands.json
    └── source
        └── main.c

My root marker is build/compile_commands.json. LanguageClient is set to automatically start. Initialization options for ccls are as follows:

{
    "initializationOptions": {
        "cache": { "directory": "/tmp/ccls" },
        "compilationDatabaseDirectory": "build",
        "client": { "snippetSupport": true },
        "clang" : { "extraArgs": ["-Wno-extra"] },
        "highlight": { "lsRanges": true }
    }
}

To recap, I start Neovim inside workspace, then :edit project_a/source/main.c and LanguageClient outputs

[LC] Project root: workspace/project_a

and everything works. Then I :edit project_b/source/main.c but the project root is not updated, thus also the compile_commands.json database is not loaded, and nothing works as expected.

Am I missing something or is this a bug/non-feature of LanguageClient?

[autozimu]

This is how this plugin works as of now.

In order to associate files of same type + project to the same language server instance, filetype is used as key mapping to language server instances.

This might be changed to use project root as key in the future. I cannot guarantee when it will come or whether it will.

As a workaround, when switching project, you can run :LanguageClientStop, :LanguageClientStart to start the language server for project b. Alternatively running different neovim session for different project.