From 1110837d0ec9eafcb523459d0a34f8970bbd8544 Mon Sep 17 00:00:00 2001
From: Jan Kassens <jan@kassens.net>
Date: Tue, 29 Dec 2020 17:29:15 +0000
Subject: [PATCH 1/2] Clarify fingerprint log messages

---
 src/cargo/core/compiler/fingerprint.rs | 26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/cargo/core/compiler/fingerprint.rs b/src/cargo/core/compiler/fingerprint.rs
index a45dee17b19..7c6a26ff365 100644
--- a/src/cargo/core/compiler/fingerprint.rs
+++ b/src/cargo/core/compiler/fingerprint.rs
@@ -817,9 +817,9 @@ impl Fingerprint {
         }
         if self.features != old.features {
             bail!(
-                "features have changed: {} != {}",
-                self.features,
-                old.features
+                "features have changed: previously {}, now {}",
+                old.features,
+                self.features
             )
         }
         if self.target != old.target {
@@ -833,9 +833,9 @@ impl Fingerprint {
         }
         if self.rustflags != old.rustflags {
             bail!(
-                "RUSTFLAGS has changed: {:?} != {:?}",
-                self.rustflags,
-                old.rustflags
+                "RUSTFLAGS has changed: previously {:?}, now {:?}",
+                old.rustflags,
+                self.rustflags
             )
         }
         if self.metadata != old.metadata {
@@ -853,7 +853,7 @@ impl Fingerprint {
             match (new, old) {
                 (LocalFingerprint::Precalculated(a), LocalFingerprint::Precalculated(b)) => {
                     if a != b {
-                        bail!("precalculated components have changed: {} != {}", a, b)
+                        bail!("precalculated components have changed: previously {}, now {}", b, a)
                     }
                 }
                 (
@@ -861,7 +861,7 @@ impl Fingerprint {
                     LocalFingerprint::CheckDepInfo { dep_info: bdep },
                 ) => {
                     if adep != bdep {
-                        bail!("dep info output changed: {:?} != {:?}", adep, bdep)
+                        bail!("dep info output changed: previously {:?}, now {:?}", bdep, adep)
                     }
                 }
                 (
@@ -875,13 +875,13 @@ impl Fingerprint {
                     },
                 ) => {
                     if aout != bout {
-                        bail!("rerun-if-changed output changed: {:?} != {:?}", aout, bout)
+                        bail!("rerun-if-changed output changed: previously {:?}, now {:?}", bout, aout)
                     }
                     if apaths != bpaths {
                         bail!(
-                            "rerun-if-changed output changed: {:?} != {:?}",
-                            apaths,
+                            "rerun-if-changed output changed: previously {:?}, now {:?}",
                             bpaths,
+                            apaths,
                         )
                     }
                 }
@@ -896,11 +896,11 @@ impl Fingerprint {
                     },
                 ) => {
                     if *akey != *bkey {
-                        bail!("env vars changed: {} != {}", akey, bkey);
+                        bail!("env vars changed: previously {}, now {}", bkey, akey);
                     }
                     if *avalue != *bvalue {
                         bail!(
-                            "env var `{}` changed: previously {:?} now {:?}",
+                            "env var `{}` changed: previously {:?}, now {:?}",
                             akey,
                             bvalue,
                             avalue

From 4538ade2d55d7353cfac8a0ce320e3c4a29bc450 Mon Sep 17 00:00:00 2001
From: Jan Kassens <jan@kassens.net>
Date: Tue, 29 Dec 2020 12:42:28 -0500
Subject: [PATCH 2/2] cargo fmt

---
 src/cargo/core/compiler/fingerprint.rs | 18 +++++++++++++++---
 1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/src/cargo/core/compiler/fingerprint.rs b/src/cargo/core/compiler/fingerprint.rs
index 7c6a26ff365..5077c33645f 100644
--- a/src/cargo/core/compiler/fingerprint.rs
+++ b/src/cargo/core/compiler/fingerprint.rs
@@ -853,7 +853,11 @@ impl Fingerprint {
             match (new, old) {
                 (LocalFingerprint::Precalculated(a), LocalFingerprint::Precalculated(b)) => {
                     if a != b {
-                        bail!("precalculated components have changed: previously {}, now {}", b, a)
+                        bail!(
+                            "precalculated components have changed: previously {}, now {}",
+                            b,
+                            a
+                        )
                     }
                 }
                 (
@@ -861,7 +865,11 @@ impl Fingerprint {
                     LocalFingerprint::CheckDepInfo { dep_info: bdep },
                 ) => {
                     if adep != bdep {
-                        bail!("dep info output changed: previously {:?}, now {:?}", bdep, adep)
+                        bail!(
+                            "dep info output changed: previously {:?}, now {:?}",
+                            bdep,
+                            adep
+                        )
                     }
                 }
                 (
@@ -875,7 +883,11 @@ impl Fingerprint {
                     },
                 ) => {
                     if aout != bout {
-                        bail!("rerun-if-changed output changed: previously {:?}, now {:?}", bout, aout)
+                        bail!(
+                            "rerun-if-changed output changed: previously {:?}, now {:?}",
+                            bout,
+                            aout
+                        )
                     }
                     if apaths != bpaths {
                         bail!(