Although not directly useful to users in most cases, the Language Server console view is extremely valuable when we need to troubleshoot issues with the language servers.
The state of the servers is visible, stop and restart is available with a right-click, and you can enable different levels of tracing:
The communication details between the IDE and the language servers are seen in the "LSP consoles" pane. In verbose mode, the messages can be expanded for more details:
If the language server logs messages via window/logMessage, you can see them in the Logs tab:
When a language server is started, several actions are available, like stopping the language server or copying the command starting the language server :
The preference page under Preferences | Languages & Frameworks | Language Servers allows power users
to configure mappings, language servers debugging and tracing:
The Mappings tab shows the file associations with the language server:
The Debug tab allows to configure language servers debugging and tracing:
The standard preference page under Preferences | Inlay Hints allows to configure LSP Codelens:
You can configure LSP CodeLens on the Top:
or configure LSP CodeLens on the Right:
The LSP formatting support can be done with the standard Reformat Code and Reformat File actions.
The following LSP features are integrated with the standard Find Usages menu (provided they're supported by the underlying language server):
If the language server can support workspace/willRenameFiles, when a file is
renamed inside IntelliJ IDEA, LSP4IJ can consume it and applies the WorkspaceEdit
to apply some refactoring.
LSP4IJ provides experimental support for LSP Semantic Tokens.
LSP4IJ provides default colors for semantic tokens, configurable in Editor / Color Scheme / Language Server:
You can see the mapping between token types/modifiers and IntelliJ's TextAttributeKey on the color settings page (e.g., Class declaration) in DefaultSemanticTokensColorsProvider section.
The Semantic Tokens Inspector allows you to understand semantic coloring via LSP semantic tokens support. You can open the inspector
with the menu View / Tool Window / Semantic Tokens Inspector:
Once the inspector is open, it tracks all calls to semantic tokens. If a file must be colored via semantic tokens, it appears in a tab of the inspector and must display information on the TextAttributeKeys to use and the token types / modifiers decoded that you can select in the left panel via the checkboxes:
If the Semantic Tokens doesn't show the expected result, please check that:
- show in the LSP console that your language server reports
LSP request
textDocument/semanticTokens/full - uses the Semantic Tokens Inspector to understand more how the file content is tokenized. Problem could come if LSP4IJ doesn't support some token types / modifiers.