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diff --git a/docs/images/debugger6.jpg b/docs/images/debugger6.jpg Binary files differdeleted file mode 100644 index e89346e5f..000000000 --- a/docs/images/debugger6.jpg +++ /dev/null diff --git a/docs/tools/debugger.md b/docs/tools/debugger.md index a6aed4711..0edbfe8a6 100644 --- a/docs/tools/debugger.md +++ b/docs/tools/debugger.md @@ -1,24 +1,24 @@ ## Debugger -Deno supports [V8 Inspector Protocol](https://v8.dev/docs/inspector). +Deno supports the [V8 Inspector Protocol](https://v8.dev/docs/inspector). -It is possible to debug Deno programs using Chrome Devtools or other clients -that support the protocol (eg. VSCode). +It's possible to debug Deno programs using Chrome Devtools or other clients that +support the protocol (eg. VSCode). -To activate debugging capabilities run Deno with `--inspect` or `--inspect-brk` -flag. +To activate debugging capabilities run Deno with the `--inspect` or +`--inspect-brk` flags. -`--inspect` flag allows to attach debugger at any point in time, while -`--inspect-brk` will wait for debugger being attached and pause execution on the -first line of code. +The `--inspect` flag allows attaching the debugger at any point in time, while +`--inspect-brk` will wait for the debugger to attach and will pause execution on +the first line of code. ### Chrome Devtools -Let's try debugging a program using Chrome Devtools; for this purpose we'll use -[file_server.ts](https://deno.land/std@v0.50.0/http/file_server.ts) from `std`; +Let's try debugging a program using Chrome Devtools. For this, we'll use +[file_server.ts](https://deno.land/std@v0.50.0/http/file_server.ts) from `std`, a static file server. -Use `--inspect-brk` flag to break execution on the first line. +Use the `--inspect-brk` flag to break execution on the first line: ```shell $ deno run --inspect-brk --allow-read --allow-net https://deno.land/std@v0.50.0/http/file_server.ts @@ -37,7 +37,7 @@ It might take a few seconds after opening the devtools to load all modules.  You might notice that Devtools paused execution on the first line of -`_constants.ts` instead of `file_server.ts`. This is an expected behavior and is +`_constants.ts` instead of `file_server.ts`. This is expected behavior and is caused by the way ES modules are evaluated by V8 (`_constants.ts` is left-most, bottom-most dependency of `file_server.ts` so it is evaluated first). @@ -48,17 +48,17 @@ tree:  _Looking closely you'll find duplicate entries for each file; one written -regularly and one in italics. The former is compiled source file (so in case of -`.ts` files it will be emitted JavaScript source), while the latter is a source -map for the file._ +regularly and one in italics. The former is compiled source file (so in the case +of `.ts` files it will be emitted JavaScript source), while the latter is a +source map for the file._ -Add a breakpoint in `listenAndServe` method: +Next, add a breakpoint in the `listenAndServe` method:  -As soon as we've added the breakpoint Devtools automatically opened up source -map file, which allows us step through the actual source code that includes -types. +As soon as we've added the breakpoint Devtools automatically opened up the +source map file, which allows us step through the actual source code that +includes types. Now that we have our breakpoints set, we can resume the execution of our script so that we might inspect an incoming request. Hit the Resume script execution @@ -73,17 +73,19 @@ $ curl http://0.0.0.0:4500/  -At this point we can introspect contents of the request and go step-by-step to -debug the code. +At this point we can introspect the contents of the request and go step-by-step +to debug the code. ### VSCode Deno can be debugged using VSCode. -Official support in plugin is being worked on - +Official support via the plugin is being worked on - https://github.com/denoland/vscode_deno/issues/12 -We can still attach debugger by manually providing a `launch.json` config: +We can still attach the debugger by manually providing a +[`launch.json`](https://code.visualstudio.com/docs/editor/debugging#_launch-configurations) +config: ```json { @@ -95,16 +97,17 @@ We can still attach debugger by manually providing a `launch.json` config: "request": "launch", "cwd": "${workspaceFolder}", "runtimeExecutable": "deno", - "runtimeArgs": ["run", "--inspect-brk", "-A", "<entry_point>"], + "runtimeArgs": ["run", "--inspect-brk", "-A", "${file}"], "port": 9229 } ] } ``` -**NOTE**: Replace `<entry_point>` with actual script name. +**NOTE**: This uses the file you have open as the entry point; replace `${file}` +with a script name if you want a fixed entry point. -This time let's try with local source file, create `server.ts`: +Let's try out debugging a local source file. Create `server.ts`: ```ts import { serve } from "https://deno.land/std@v0.50.0/http/server.ts"; @@ -116,9 +119,7 @@ for await (const req of server) { } ``` -Change `<entry_point>` to `server.ts` and run created configuration: - - +Then we can set a breakpoint, and run the created configuration:  @@ -126,19 +127,19 @@ Change `<entry_point>` to `server.ts` and run created configuration: You can debug Deno using your JetBrains IDE by right-clicking the file you want to debug and selecting the `Debug 'Deno: <file name>'` option. This will create -a run/debug configuration which has no permission flags set, so to change that -you need to modify the run/debug configuration and change the `Arguments` field -with the required flags. +a run/debug configuration with no permission flags set. To configure these flags +edit the run/debug configuration and modify the `Arguments` field with the +required flags. ### Other -Any client that implements Devtools protocol should be able to connect to Deno -process. +Any client that implements the Devtools protocol should be able to connect to a +Deno process. ### Limitations -Devtools support is still immature, there are some functionalities that are -known to be missing/buggy: +Devtools support is still immature. There is some functionality that is known to +be missing or buggy: -- autocomplete in Devtools' Console causes Deno process to exit +- autocomplete in Devtools' console causes the Deno process to exit - profiling and memory dumps might not work correctly |
