never try twice to infer a target

1 files changed, 8 insertions, 0 deletions

diff --git a/src/makefile/mod.rs b/src/makefile/mod.rs
index d7cc25e..7cc16c5 100644
--- a/src/makefile/mod.rs
+++ b/src/makefile/mod.rs
@@ -1,4 +1,5 @@
 use std::cell::{Cell, RefCell};
+use std::collections::HashSet;
 use std::env;
 use std::fmt;
 use std::path::{Path, PathBuf};
@@ -44,6 +45,7 @@ pub struct Makefile<'a> {
     targets: DynamicTargetSet,
     pub first_non_special_target: Option<String>,
     args: &'a Args,
+    already_inferred: RefCell<HashSet<String>>,
     // TODO borrow warnings from Python version
 }
 
@@ -123,6 +125,7 @@ impl<'a> Makefile<'a> {
             targets,
             first_non_special_target,
             args,
+            already_inferred: Default::default(),
         }
     }
 
@@ -170,6 +173,10 @@ impl<'a> Makefile<'a> {
         if banned_names.contains(&name) {
             bail!("no infinite recursion allowed");
         }
+        if self.already_inferred.borrow().contains(name) {
+            return Ok(());
+        }
+        self.already_inferred.borrow_mut().insert(name.to_owned());
         log::trace!("inferring {}, stack = {:?}", name, banned_names);
         let mut new_target = None;
 
@@ -519,6 +526,7 @@ mod test {
             targets: Default::default(),
             first_non_special_target: None,
             args: &args,
+            already_inferred: Default::default(),
         };
 
         let target = file.get_target("this-is-a-test-case")?;