Update docs to include note about ANSI diagnostics

Author: ian-h-chamberlain

crates/rust-analyzer/src/config.rs

@@ -159,7 +159,9 @@ config_data! {
         checkOnSave_noDefaultFeatures: Option<bool>      = "null",
         /// Override the command rust-analyzer uses instead of `cargo check` for
         /// diagnostics on save. The command is required to output json and
-        /// should therefore include `--message-format=json` or a similar option.
+        /// should therefore include `--message-format=json` or a similar option
+        /// (for colored diagnostics, use
+        /// `--message-format=json-diagnostic-rendered-ansi`).
         ///
         /// If you're changing this because you're using some tool wrapping
         /// Cargo, you might also want to change

docs/user/generated_config.adoc

@@ -173,7 +173,9 @@ Whether to pass `--no-default-features` to Cargo. Defaults to
 --
 Override the command rust-analyzer uses instead of `cargo check` for
 diagnostics on save. The command is required to output json and
-should therefore include `--message-format=json` or a similar option.
+should therefore include `--message-format=json` or a similar option
+(for colored diagnostics, use
+`--message-format=json-diagnostic-rendered-ansi`).
 
 If you're changing this because you're using some tool wrapping
 Cargo, you might also want to change

editors/code/package.json

@@ -639,7 +639,7 @@
                     ]
                 },
                 "rust-analyzer.checkOnSave.overrideCommand": {
-                    "markdownDescription": "Override the command rust-analyzer uses instead of `cargo check` for\ndiagnostics on save. The command is required to output json and\nshould therefore include `--message-format=json` or a similar option.\n\nIf you're changing this because you're using some tool wrapping\nCargo, you might also want to change\n`#rust-analyzer.cargo.buildScripts.overrideCommand#`.\n\nIf there are multiple linked projects, this command is invoked for\neach of them, with the working directory being the project root\n(i.e., the folder containing the `Cargo.toml`).\n\nAn example command would be:\n\n```bash\ncargo check --workspace --message-format=json --all-targets\n```\n.",
+                    "markdownDescription": "Override the command rust-analyzer uses instead of `cargo check` for\ndiagnostics on save. The command is required to output json and\nshould therefore include `--message-format=json` or a similar option\n(for colored diagnostics, use\n`--message-format=json-diagnostic-rendered-ansi`).\n\nIf you're changing this because you're using some tool wrapping\nCargo, you might also want to change\n`#rust-analyzer.cargo.buildScripts.overrideCommand#`.\n\nIf there are multiple linked projects, this command is invoked for\neach of them, with the working directory being the project root\n(i.e., the folder containing the `Cargo.toml`).\n\nAn example command would be:\n\n```bash\ncargo check --workspace --message-format=json --all-targets\n```\n.",
                     "default": null,
                     "type": [
                         "null",