Rollup merge of rust-lang#63927 - mark-i-m:filter-spurious, r=ehuss

Filter linkcheck spurious failure

r? @ehuss

cc @spastorino

Basically, we filter errors with messages containing "timed out"... a bit of a hack, but hopefully this will be functionality built into linkcheck soon.

src/tools/rustbook/src/main.rs

@@ -1,18 +1,19 @@
-use clap::{crate_version};
+use clap::crate_version;
 
 use std::env;
 use std::path::{Path, PathBuf};
 
-use clap::{App, ArgMatches, SubCommand, AppSettings};
+use clap::{App, AppSettings, ArgMatches, SubCommand};
 
+use mdbook::errors::Result as Result3;
 use mdbook::MDBook;
-use mdbook::errors::{Result as Result3};
 
+#[cfg(feature = "linkcheck")]
+use failure::Error;
 #[cfg(feature = "linkcheck")]
 use mdbook::renderer::RenderContext;
 #[cfg(feature = "linkcheck")]
 use mdbook_linkcheck::{self, errors::BrokenLinks};
-use failure::Error;
 
 fn main() {
     let d_message = "-d, --dest-dir=[dest-dir]
@@ -21,18 +22,22 @@ fn main() {
 'A directory for your book{n}(Defaults to Current Directory when omitted)'";
 
     let matches = App::new("rustbook")
-                    .about("Build a book with mdBook")
-                    .author("Steve Klabnik <[email protected]>")
-                    .version(&*format!("v{}", crate_version!()))
-                    .setting(AppSettings::SubcommandRequired)
-                    .subcommand(SubCommand::with_name("build")
-                        .about("Build the book from the markdown files")
-                        .arg_from_usage(d_message)
-                        .arg_from_usage(dir_message))
-                    .subcommand(SubCommand::with_name("linkcheck")
-                        .about("Run linkcheck with mdBook 3")
-                        .arg_from_usage(dir_message))
-                    .get_matches();
+        .about("Build a book with mdBook")
+        .author("Steve Klabnik <[email protected]>")
+        .version(&*format!("v{}", crate_version!()))
+        .setting(AppSettings::SubcommandRequired)
+        .subcommand(
+            SubCommand::with_name("build")
+                .about("Build the book from the markdown files")
+                .arg_from_usage(d_message)
+                .arg_from_usage(dir_message),
+        )
+        .subcommand(
+            SubCommand::with_name("linkcheck")
+                .about("Run linkcheck with mdBook 3")
+                .arg_from_usage(dir_message),
+        )
+        .get_matches();
 
     // Check which subcomamnd the user ran...
     match matches.subcommand() {
@@ -46,23 +51,44 @@ fn main() {
 
                 ::std::process::exit(101);
             }
-        },
+        }
         ("linkcheck", Some(sub_matches)) => {
-            if let Err(err) = linkcheck(sub_matches) {
-                eprintln!("Error: {}", err);
-
-                #[cfg(feature = "linkcheck")]
-                {
-                    if let Ok(broken_links) = err.downcast::<BrokenLinks>() {
-                        for cause in broken_links.links().iter() {
-                            eprintln!("\tCaused By: {}", cause);
-                        }
+            #[cfg(feature = "linkcheck")]
+            {
+                if let Err(err) = linkcheck(sub_matches) {
+                    eprintln!("Error: {}", err);
+
+                    // HACK: ignore timeouts
+                    let actually_broken = err
+                        .downcast::<BrokenLinks>()
+                        .map(|broken_links| {
+                            broken_links
+                                .links()
+                                .iter()
+                                .inspect(|cause| eprintln!("\tCaused By: {}", cause))
+                                .fold(false, |already_broken, cause| {
+                                    already_broken || !format!("{}", cause).contains("timed out")
+                                })
+                        })
+                        .unwrap_or(false);
+
+                    if actually_broken {
+                        std::process::exit(101);
+                    } else {
+                        std::process::exit(0);
                     }
                 }
+            }
 
-                ::std::process::exit(101);
+            #[cfg(not(feature = "linkcheck"))]
+            {
+                // This avoids the `unused_binding` lint.
+                println!(
+                    "mdbook-linkcheck is disabled, but arguments were passed: {:?}",
+                    sub_matches
+                );
             }
-        },
+        }
         (_, _) => unreachable!(),
     };
 }
@@ -77,12 +103,6 @@ pub fn linkcheck(args: &ArgMatches<'_>) -> Result<(), Error> {
     mdbook_linkcheck::check_links(&render_ctx)
 }
 
-#[cfg(not(feature = "linkcheck"))]
-pub fn linkcheck(_args: &ArgMatches<'_>) -> Result<(), Error> {
-    println!("mdbook-linkcheck is disabled.");
-    Ok(())
-}
-
 // Build command implementation
 pub fn build(args: &ArgMatches<'_>) -> Result3<()> {
     let book_dir = get_book_dir(args);