VS Code

[lhstrh]

This is a draft pull request to track changes in the vscode branch.

The process for opening the extension should be straightforward. As stated by Alexander:

Simply run: gradlew startCode. You also need mvn on your path and if Java 11 is not your default JDK you need to prepend something like this: JAVA_HOME=/usr/lib/jvm/java-11-openjdk-amd64/

Features currently provided include:

• Highlighting
  • Includes: Syntax highlighting, semantic highlighting
  • Triggered by: Opening a non-empty file with the file extension .lf. Full highlighting requires a target specification at the top of the file.
• Building upon request by the user
  • Triggered by: Pressing Ctrl+Shift+P and entering the command "Build Lingua Franca" while an LF file is active in the editor
• C++ validation
  • Triggered by: Opening a non-empty file with a C++ syntax error but no LF syntax errors and saving it, after a version of it has already been built. (It must be built beforehand because access to the CMake cache is required.)
• Diagrams
  • Triggered by: Opening a Lingua Franca source file and clicking the diagrams icon:

The Xtext team has already implemented many useful services, including the following. (It is not yet clear if all of them work.)

• Content assist
• Folding ranges
• Find references
• Quick fixes (beta)
• Formatting
• Hover
• Highlight all references to the current symbol
• Rename symbols
• Get workspace symbols

Here is a list of current action items in this branch.

Required before the first release of the extension:

• Correctly resolve dependencies that can only be retrieved using Gradle
• Build in a way that allows faster development than fully generating the LDS jar
• Syntax highlighting
• Semantic highlighting
• VS Code: Perform a full build iff the user requests it

For desired features that will not be implemented as part of this PR, see: https://github.com/lf-lang/lingua-franca/issues/614