saving non-Java file under source folder leads to rebuild

[angelozerr]

When I create a foo.ts file in src folder, and I save it, there is a workspace/didChangeWatchedFiles which seems retrigger the project build.

It is because JDT LS returns this following glob pattern:

{
    "globPattern": "**/src/**"
}

@rgrunber told me that you did that perhaps to support generated files. I wonder if you should avoid triggering a build if it is not a java files?

Here my LSP traces:

[Trace - 4:24:49 PM] Sending notification 'workspace/didChangeWatchedFiles'.
Params: {
    "changes": [
        {
            "uri": "file:///c%3A/Users/azerr/git/intellij-quarkus/projects/lsp4mp/projects/maven/microprofile-health-3/src/main/foo.ts",
            "type": 2
        }
    ]
}


[Trace - 4:24:50 PM] Received notification 'textDocument/publishDiagnostics'.
Params: {
    "uri": "file:///C:/Users/azerr/git/intellij-quarkus/projects/lsp4mp/projects/maven/microprofile-health-3/",
    "diagnostics": []
}


[Trace - 4:24:50 PM] Received notification 'textDocument/publishDiagnostics'.
Params: {
    "uri": "file:///C:/Users/azerr/git/intellij-quarkus/projects/lsp4mp/projects/maven/microprofile-health-3/pom.xml",
    "diagnostics": []
}


[Trace - 4:24:50 PM] Received request 'window/workDoneProgress/create - (55)'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5"
}


[Trace - 4:24:50 PM] Sending response 'window/workDoneProgress/create - (55)'. Processing request took 0ms
No result returned.


[Trace - 4:24:50 PM] Received notification '$/progress'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5",
    "value": {
        "kind": "begin",
        "title": "Building",
        "message": "Building"
    }
}


[Trace - 4:24:50 PM] Received notification '$/progress'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5",
    "value": {
        "kind": "report",
        "message": "Building - 0% ",
        "percentage": 0
    }
}


[Trace - 4:24:50 PM] Received notification '$/progress'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5",
    "value": {
        "kind": "report",
        "message": "Building - 75% Refreshing '/microprofile-health-3'.",
        "percentage": 75
    }
}


[Trace - 4:24:50 PM] Received notification '$/progress'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5",
    "value": {
        "kind": "report",
        "message": "Building - 77% Refreshing '/microprofile-health-3'.",
        "percentage": 76
    }
}


[Trace - 4:24:50 PM] Received notification '$/progress'.
Params: {
    "token": "78f4c054-433c-4ceb-8434-fe76c972e3c5",
    "value": {
        "kind": "end",
        "message": "Building"
    }
}


[Trace - 4:29:50 PM] Received request 'window/workDoneProgress/create - (56)'.
Params: {
    "token": "fbd7a42c-2eb2-47b7-b0bf-e5868cf7ddd1"
}


[Trace - 4:29:50 PM] Sending response 'window/workDoneProgress/create - (56)'. Processing request took 0ms
No result returned.


[Trace - 4:29:50 PM] Received notification '$/progress'.
Params: {
    "token": "fbd7a42c-2eb2-47b7-b0bf-e5868cf7ddd1",
    "value": {
        "kind": "begin",
        "title": "Building",
        "message": "Building"
    }
}


[Trace - 4:29:50 PM] Received notification '$/progress'.
Params: {
    "token": "fbd7a42c-2eb2-47b7-b0bf-e5868cf7ddd1",
    "value": {
        "kind": "report",
        "message": "Building - 0% ",
        "percentage": 0
    }
}


[Trace - 4:29:50 PM] Received notification '$/progress'.
Params: {
    "token": "fbd7a42c-2eb2-47b7-b0bf-e5868cf7ddd1",
    "value": {
        "kind": "end",
        "message": "Building"
    }
}

[rgrunber]

I'm able to reproduce. Here's what I see so far :

The reason the build is triggered seems like a side effect.

eclipse.jdt.ls/org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/managers/StandardProjectsManager.java

Line 223 in df60479

IResource resource = JDTUtils.getFileOrFolder(uriString);

The code ends up there and that method triggers the diagnostics clearing + the rebuild at :

eclipse.jdt.ls/org.eclipse.jdt.ls.core/src/org/eclipse/jdt/ls/core/internal/JDTUtils.java

Line 1260 in df60479

parent.refreshLocal(DEPTH_ONE, null);

Maybe we need to find a way to avoid that side effect. I'll need to look further to figure out how that triggers the rebuild. I'm thinking of examples like Protobuf, where being able to trigger rebuilds from changes to non-Java files is needed, but if this doesn't contribute to that, then we should prevent it from happening.

[rgrunber]

Nevermind. @snjeza pointed out that this is an incremental autobuild. No other classfiles get rebuilt (I checked timestamps). Simply the non-Java file gets updated (copied) into the output folder.

I think we can probably close this, although it's a bit strange for the autobuild side effect to be purely a result of refreshing the parent in a utility method that simply returns the resource of a uri.

[huangfeiyu]

@rgrunber I am wonder may the side effect caused dead loop. Say in a maven project, front engineer put some front source files (less, ts etc) in src/main/webapp/, and use maven plugin frontend-maven-plugin to build the front files, the target directory of the front build may still in src/main/webapp/, if the target file trigger auto build too, there is ever ending build.

[rgrunber]

A similar issue was reported at redhat-developer/vscode-java#3639 . Although that one seems different in that the file being refreshed is in the target folder, though it is a non-source file generated by the build.