rustdoc: Represent --output-format=json coverage and ir differently

src/librustdoc/config.rs

@@ -29,33 +29,18 @@ use crate::passes::{self, Condition};
 use crate::scrape_examples::{AllCallLocations, ScrapeExamplesOptions};
 use crate::{html, opts, theme};
 
-#[derive(Clone, Copy, PartialEq, Eq, Debug, Default)]
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
 pub(crate) enum OutputFormat {
-    Json,
-    #[default]
+    /// `--output-format=json` without `--show-coverage`.
+    ///
+    /// JSON description of crate API.
+    IrJson,
+    /// `--output-format=json` with `--show-coverage`.
+    CoverageJson,
     Html,
     Doctest,
 }
 
-impl OutputFormat {
-    pub(crate) fn is_json(&self) -> bool {
-        matches!(self, OutputFormat::Json)
-    }
-}
-
-impl TryFrom<&str> for OutputFormat {
-    type Error = String;
-
-    fn try_from(value: &str) -> Result<Self, Self::Error> {
-        match value {
-            "json" => Ok(OutputFormat::Json),
-            "html" => Ok(OutputFormat::Html),
-            "doctest" => Ok(OutputFormat::Doctest),
-            _ => Err(format!("unknown output format `{value}`")),
-        }
-    }
-}
-
 /// Either an input crate, markdown file, or nothing (--merge=finalize).
 pub(crate) enum InputMode {
     /// The `--merge=finalize` step does not need an input crate to rustdoc.
@@ -329,7 +314,8 @@ pub(crate) enum EmitType {
     HtmlStaticFiles,
     HtmlNonStaticFiles,
     // not explicitly nameable by the user for now
-    JsonFiles,
+    IrJsonFiles,
+    CoverageJsonFiles,
     DepInfo(Option<OutFileName>),
 }
 
@@ -338,7 +324,8 @@ impl fmt::Display for EmitType {
         f.write_str(match self {
             Self::HtmlStaticFiles => "html-static-files",
             Self::HtmlNonStaticFiles => "html-non-static-files",
-            Self::JsonFiles => "json-files",
+            Self::IrJsonFiles => "ir-json-files",
+            Self::CoverageJsonFiles => "coverage-json-files",
             Self::DepInfo(_) => "dep-info",
         })
     }
@@ -479,40 +466,48 @@ impl Options {
 
         let show_coverage = matches.opt_present("show-coverage");
         let output_format_s = matches.opt_str("output-format");
-        let output_format = match output_format_s {
-            Some(ref s) => match OutputFormat::try_from(s.as_str()) {
-                Ok(out_fmt) => out_fmt,
-                Err(e) => dcx.fatal(e),
-            },
-            None => OutputFormat::default(),
+        let output_format = match output_format_s.as_deref() {
+            None | Some("html") => OutputFormat::Html,
+            Some("json") => {
+                if show_coverage {
+                    OutputFormat::CoverageJson
+                } else {
+                    OutputFormat::IrJson
+                }
+            }
+            Some("doctest") => OutputFormat::Doctest,
+            Some(other) => dcx.fatal(format!("unknown output format `{other}`")),
         };
 
-        // check for `--output-format=json`
+        // check for `--output-format` stability, and compatibility with `--show-coverage`
         match (
             output_format_s.as_ref().map(|_| output_format),
             show_coverage,
             nightly_options::is_unstable_enabled(matches),
         ) {
-            (None | Some(OutputFormat::Json), true, _) => {}
+            (None | Some(OutputFormat::CoverageJson), true, _) => {}
             (_, true, _) => {
                 dcx.fatal(format!(
                     "`--output-format={}` is not supported for the `--show-coverage` option",
-                    output_format_s.unwrap_or_default(),
+                    output_format_s.expect("checked for none above"),
                 ));
             }
             // If `-Zunstable-options` is used, nothing to check after this point.
             (_, false, true) => {}
             (None | Some(OutputFormat::Html), false, _) => {}
-            (Some(OutputFormat::Json), false, false) => {
+            (Some(OutputFormat::IrJson), false, false) => {
                 dcx.fatal(
-                    "the -Z unstable-options flag must be passed to enable --output-format for documentation generation (see https://github.com/rust-lang/rust/issues/76578)",
+                    "the -Z unstable-options flag must be passed to enable --output-format=json for documentation generation (see https://github.com/rust-lang/rust/issues/76578)",
                 );
             }
             (Some(OutputFormat::Doctest), false, false) => {
                 dcx.fatal(
-                    "the -Z unstable-options flag must be passed to enable --output-format for documentation generation (see https://github.com/rust-lang/rust/issues/134529)",
+                    "the -Z unstable-options flag must be passed to enable --output-format=doctest (see https://github.com/rust-lang/rust/issues/134529)",
                 );
             }
+            (Some(OutputFormat::CoverageJson), false, _) => {
+                unreachable!("CoverageJson is only possible when show_coverage is true")
+            }
         }
 
         let mut emit = FxIndexMap::default();
@@ -531,18 +526,18 @@ impl Options {
 
                 match typ {
                     EmitType::DepInfo(_) => match output_format {
-                        OutputFormat::Json | OutputFormat::Html => {}
+                        OutputFormat::Html | OutputFormat::IrJson | OutputFormat::CoverageJson => {}
                         OutputFormat::Doctest => unreachable!(),
                     },
                     EmitType::HtmlStaticFiles | EmitType::HtmlNonStaticFiles => match output_format
                     {
                         OutputFormat::Html => {}
-                        OutputFormat::Json => dcx.fatal(format!(
+                        OutputFormat::IrJson | OutputFormat::CoverageJson => dcx.fatal(format!(
                             "the `--emit={typ}` flag is not supported with `--output-format=json`",
                         )),
                         OutputFormat::Doctest => unreachable!(),
                     },
-                    EmitType::JsonFiles => unreachable!(),
+                    EmitType::IrJsonFiles | EmitType::CoverageJsonFiles => unreachable!(),
                 }
 
                 // De-duplicate emit types and the last wins.
@@ -558,7 +553,8 @@ impl Options {
         // will have already been rejected above.
         if emit.is_empty() {
             match output_format {
-                OutputFormat::Json => emit.push(EmitType::JsonFiles),
+                OutputFormat::IrJson => emit.push(EmitType::IrJsonFiles),
+                OutputFormat::CoverageJson => emit.push(EmitType::CoverageJsonFiles),
                 OutputFormat::Html => {
                     emit.push(EmitType::HtmlStaticFiles);
                     emit.push(EmitType::HtmlNonStaticFiles);

src/librustdoc/core.rs

@@ -75,8 +75,6 @@ pub(crate) struct DocContext<'tcx> {
     pub(crate) inlined: FxHashSet<ItemId>,
     /// Used by `calculate_doc_coverage`.
     pub(crate) output_format: OutputFormat,
-    /// Used by `strip_private`.
-    pub(crate) show_coverage: bool,
 }
 
 impl<'tcx> DocContext<'tcx> {
@@ -139,7 +137,7 @@ impl<'tcx> DocContext<'tcx> {
     ///
     /// If another option like `--show-coverage` is enabled, it will return `false`.
     pub(crate) fn is_json_output(&self) -> bool {
-        self.output_format.is_json() && !self.show_coverage
+        self.output_format == OutputFormat::IrJson
     }
 
     /// If `--document-private-items` was passed to rustdoc.
@@ -385,7 +383,6 @@ pub(crate) fn run_global_ctxt(
         cache: Cache::new(render_options.document_private, render_options.document_hidden),
         inlined: FxHashSet::default(),
         output_format,
-        show_coverage,
     };
 
     for cnum in tcx.crates(()) {

src/librustdoc/json/mod.rs

@@ -134,7 +134,7 @@ impl<'tcx> JsonRenderer<'tcx> {
 impl<'tcx> FormatRenderer<'tcx> for JsonRenderer<'tcx> {
     const DESCR: &'static str = "json";
     const RUN_ON_MODULE: bool = false;
-    const NON_STATIC_FILE_EMIT_TYPE: EmitType = EmitType::JsonFiles;
+    const NON_STATIC_FILE_EMIT_TYPE: EmitType = EmitType::IrJsonFiles;
 
     type ModuleData = ();
 

src/librustdoc/lib.rs

@@ -984,11 +984,13 @@ fn main_args(early_dcx: &mut EarlyDiagCtxt, at_args: &[String]) {
                         },
                     )
                 }),
-                config::OutputFormat::Json => sess.time("render_json", || {
+                config::OutputFormat::IrJson => sess.time("render_json", || {
                     run_renderer(krate, render_opts, cache, tcx, json::JsonRenderer::init)
                 }),
-                // Already handled above with doctest runners.
-                config::OutputFormat::Doctest => unreachable!(),
+                // Already handled above with doctest runners or coverage early return
+                config::OutputFormat::Doctest | config::OutputFormat::CoverageJson => {
+                    unreachable!()
+                }
             }
         })
     })

src/librustdoc/passes/calculate_doc_coverage.rs

@@ -11,6 +11,7 @@ use serde::Serialize;
 use tracing::debug;
 
 use crate::clean;
+use crate::config::OutputFormat;
 use crate::core::DocContext;
 use crate::html::markdown::{ErrorCodes, find_testable_code};
 use crate::passes::Pass;
@@ -131,8 +132,7 @@ impl CoverageCalculator<'_, '_> {
 
     fn print_results(&self) {
         let output_format = self.ctx.output_format;
-        // In this case we want to ensure that the `OutputFormat` is JSON and NOT the `DocContext`.
-        if output_format.is_json() {
+        if output_format == OutputFormat::CoverageJson {
             println!("{}", self.to_json());
             return;
         }

tests/rustdoc-ui/output-format-coveragejson-emit-depinfo.rs

@@ -0,0 +1,2 @@
+//@ compile-flags: --show-coverage --output-format=json --emit=dep-info -Zunstable-options
+//@ build-pass

tests/rustdoc-ui/output-format-coveragejson-emit-depinfo.stdout

@@ -0,0 +1 @@
+{"$DIR/output-format-coveragejson-emit-depinfo.rs":{"total":1,"with_docs":0,"total_examples":0,"with_examples":0}}

tests/rustdoc-ui/output-format-doctests-unstable.rs

@@ -0,0 +1,4 @@
+//@ compile-flags: --output-format=doctest
+pub struct Foo;
+
+//~? ERROR the -Z unstable-options flag must be passed to enable --output-format=doctest (see https://github.com/rust-lang/rust/issues/134529)

tests/rustdoc-ui/output-format-doctests-unstable.stderr

@@ -0,0 +1,2 @@
+error: the -Z unstable-options flag must be passed to enable --output-format=doctest (see https://github.com/rust-lang/rust/issues/134529)
+

tests/rustdoc-ui/output-format-irjson-emit-depinfo.rs

@@ -0,0 +1,2 @@
+//@ compile-flags: --output-format=json --emit=dep-info -Zunstable-options
+//@ build-pass

tests/rustdoc-ui/output-format-irjson-unstable.rs

@@ -0,0 +1,4 @@
+//@ compile-flags: --output-format=json
+pub struct Foo;
+
+//~? ERROR the -Z unstable-options flag must be passed to enable --output-format=json for documentation

tests/rustdoc-ui/output-format-irjson-unstable.stderr

@@ -0,0 +1,2 @@
+error: the -Z unstable-options flag must be passed to enable --output-format=json for documentation generation (see https://github.com/rust-lang/rust/issues/76578)
+

tests/rustdoc-ui/output-format-json-emit-html.html_non_static_coverage.stderr

@@ -0,0 +1,2 @@
+error: the `--emit=html-non-static-files` flag is not supported with `--output-format=json`
+

tests/rustdoc-ui/output-format-json-emit-html.html_static_coverage.stderr

@@ -0,0 +1,2 @@
+error: the `--emit=html-static-files` flag is not supported with `--output-format=json`
+

tests/rustdoc-ui/output-format-json-emit-html.rs

@@ -1,7 +1,11 @@
-//@ revisions: html_static html_non_static
+//@ revisions: html_static html_non_static html_static_coverage html_non_static_coverage
 //@ compile-flags: -Zunstable-options --output-format json
 //@[html_static] compile-flags: --emit html-static-files
+//@[html_static_coverage] compile-flags: --emit html-static-files --show-coverage
 //@[html_non_static] compile-flags:  --emit html-non-static-files
+//@[html_non_static_coverage] compile-flags:  --emit html-non-static-files --show-coverage
 
 //[html_static]~? ERROR the `--emit=html-static-files` flag is not supported with `--output-format=json`
+//[html_static_coverage]~? ERROR the `--emit=html-static-files` flag is not supported with `--output-format=json`
 //[html_non_static]~? ERROR the `--emit=html-non-static-files` flag is not supported with `--output-format=json`
+//[html_non_static_coverage]~? ERROR the `--emit=html-non-static-files` flag is not supported with `--output-format=json`

tests/rustdoc-ui/output-format-unknown.rs

@@ -0,0 +1,4 @@
+//@ compile-flags: --output-format=da-doo-ron-ron
+
+pub struct Foo;
+//~? ERROR unknown output format `da-doo-ron-ron`

tests/rustdoc-ui/output-format-unknown.stderr

@@ -0,0 +1,2 @@
+error: unknown output format `da-doo-ron-ron`
+