From a93feaf6e12bf6a14f65c7ab21c6262796315626 Mon Sep 17 00:00:00 2001
From: Will Crichton <wcrichto@cs.stanford.edu>
Date: Sat, 30 Jul 2022 21:12:04 -0700
Subject: [PATCH] Make Rustdoc exit with correct error code when scrape
 examples from invalid files

---
 src/librustdoc/scrape_examples.rs                  |  6 ++++++
 .../scrape-examples-fail-if-type-error.rs          |  7 +++++++
 .../scrape-examples-fail-if-type-error.stderr      | 14 ++++++++++++++
 3 files changed, 27 insertions(+)
 create mode 100644 src/test/rustdoc-ui/scrape-examples-fail-if-type-error.rs
 create mode 100644 src/test/rustdoc-ui/scrape-examples-fail-if-type-error.stderr

diff --git a/src/librustdoc/scrape_examples.rs b/src/librustdoc/scrape_examples.rs
index fd0b19034a25..0d9684025033 100644
--- a/src/librustdoc/scrape_examples.rs
+++ b/src/librustdoc/scrape_examples.rs
@@ -304,6 +304,12 @@ pub(crate) fn run(
         let mut finder = FindCalls { calls: &mut calls, tcx, map: tcx.hir(), cx, target_crates };
         tcx.hir().visit_all_item_likes_in_crate(&mut finder);
 
+        // The visitor might have found a type error, which we need to
+        // promote to a fatal error
+        if tcx.sess.diagnostic().has_errors_or_lint_errors().is_some() {
+            return Err(String::from("Compilation failed, aborting rustdoc"));
+        }
+
         // Sort call locations within a given file in document order
         for fn_calls in calls.values_mut() {
             for file_calls in fn_calls.values_mut() {
diff --git a/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.rs b/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.rs
new file mode 100644
index 000000000000..8f4fde96d7e4
--- /dev/null
+++ b/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.rs
@@ -0,0 +1,7 @@
+// check-fail
+// compile-flags: -Z unstable-options --scrape-examples-output-path {{build-base}}/t.calls --scrape-examples-target-crate foobar
+
+pub fn foo() {
+  INVALID_FUNC();
+  //~^ ERROR could not resolve path
+}
diff --git a/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.stderr b/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.stderr
new file mode 100644
index 000000000000..750aa3207194
--- /dev/null
+++ b/src/test/rustdoc-ui/scrape-examples-fail-if-type-error.stderr
@@ -0,0 +1,14 @@
+error[E0433]: failed to resolve: could not resolve path `INVALID_FUNC`
+  --> $DIR/scrape-examples-fail-if-type-error.rs:5:3
+   |
+LL |   INVALID_FUNC();
+   |   ^^^^^^^^^^^^ could not resolve path `INVALID_FUNC`
+   |
+   = note: this error was originally ignored because you are running `rustdoc`
+   = note: try running again with `rustc` or `cargo check` and you may get a more detailed error
+
+error: Compilation failed, aborting rustdoc
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0433`.