Track changes in fuzzy-matching in error messages

34 files changed, 148 insertions, 44 deletions

diff --git a/testsuite/tests/ghc-regress/arrows/should_fail/arrowfail002.stderr b/testsuite/tests/ghc-regress/arrows/should_fail/arrowfail002.stderr
index c653acc339..935d7e38a6 100644
--- a/testsuite/tests/ghc-regress/arrows/should_fail/arrowfail002.stderr
+++ b/testsuite/tests/ghc-regress/arrows/should_fail/arrowfail002.stderr
@@ -1,2 +1,4 @@
 
-arrowfail002.hs:6:17: Not in scope: `x'
+arrowfail002.hs:6:17:
+    Not in scope: `x'
+    Perhaps you meant one of these: `f' (line 7), `g' (line 6)
diff --git a/testsuite/tests/ghc-regress/driver/1372/1372.stderr b/testsuite/tests/ghc-regress/driver/1372/1372.stderr
index f06f294dae..f96bc9e9ff 100644
--- a/testsuite/tests/ghc-regress/driver/1372/1372.stderr
+++ b/testsuite/tests/ghc-regress/driver/1372/1372.stderr
@@ -1,2 +1,6 @@
 
-Main.hs:5:5: Not in scope: data constructor `T'
+Main.hs:5:5:
+    Not in scope: data constructor `T'
+    Perhaps you meant one of these:
+      `GT' (imported from Prelude), `LT' (imported from Prelude),
+      `T'' (imported from A)
diff --git a/testsuite/tests/ghc-regress/ghci/prog009/ghci.prog009.stderr b/testsuite/tests/ghc-regress/ghci/prog009/ghci.prog009.stderr
index 17466af7ec..484a1b9f27 100644
--- a/testsuite/tests/ghc-regress/ghci/prog009/ghci.prog009.stderr
+++ b/testsuite/tests/ghc-regress/ghci/prog009/ghci.prog009.stderr
@@ -1,6 +1,8 @@
 
 A.hs:1:16: parse error on input `where'
 
-<interactive>:1:1: Not in scope: `yan'
+<interactive>:1:1:
+    Not in scope: `yan'
+    Perhaps you meant `tan' (imported from Prelude)
 
 A.hs:1:16: parse error on input `where'
diff --git a/testsuite/tests/ghc-regress/ghci/scripts/ghci036.stderr b/testsuite/tests/ghc-regress/ghci/scripts/ghci036.stderr
index 1fe34062af..dcf53da5af 100644
--- a/testsuite/tests/ghc-regress/ghci/scripts/ghci036.stderr
+++ b/testsuite/tests/ghc-regress/ghci/scripts/ghci036.stderr
@@ -7,7 +7,9 @@
 
 <interactive>:1:1: Not in scope: `nub'
 
-<interactive>:1:1: Not in scope: `nub'
+<interactive>:1:1:
+    Not in scope: `nub'
+    Perhaps you meant `L.nub' (imported from Data.List)
 
 <interactive>:1:1:
     Failed to load interface for `L':
diff --git a/testsuite/tests/ghc-regress/module/mod101.stderr b/testsuite/tests/ghc-regress/module/mod101.stderr
index 1d0b237de9..662c38e89a 100644
--- a/testsuite/tests/ghc-regress/module/mod101.stderr
+++ b/testsuite/tests/ghc-regress/module/mod101.stderr
@@ -1,2 +1,4 @@
 
-mod101.hs:8:5: Not in scope: data constructor `ConB'
+mod101.hs:8:5:
+    Not in scope: data constructor `ConB'
+    Perhaps you meant `ConA' (imported from Mod101_AuxB)
diff --git a/testsuite/tests/ghc-regress/module/mod102.stderr b/testsuite/tests/ghc-regress/module/mod102.stderr
index 811500b6f1..60f7b28ab2 100644
--- a/testsuite/tests/ghc-regress/module/mod102.stderr
+++ b/testsuite/tests/ghc-regress/module/mod102.stderr
@@ -1,2 +1,4 @@
 
-mod102.hs:8:5: Not in scope: `methB'
+mod102.hs:8:5:
+    Not in scope: `methB'
+    Perhaps you meant `methA' (imported from Mod102_AuxB)
diff --git a/testsuite/tests/ghc-regress/module/mod121.stderr b/testsuite/tests/ghc-regress/module/mod121.stderr
index f6f2f4c354..7c2cf2cc9d 100644
--- a/testsuite/tests/ghc-regress/module/mod121.stderr
+++ b/testsuite/tests/ghc-regress/module/mod121.stderr
@@ -1,2 +1,4 @@
 
-mod121.hs:5:5: Not in scope: `m2'
+mod121.hs:5:5:
+    Not in scope: `m2'
+    Perhaps you meant `m1' (imported from Mod121_A)
diff --git a/testsuite/tests/ghc-regress/module/mod125.stderr b/testsuite/tests/ghc-regress/module/mod125.stderr
index b2f7fa4503..a76c7513eb 100644
--- a/testsuite/tests/ghc-regress/module/mod125.stderr
+++ b/testsuite/tests/ghc-regress/module/mod125.stderr
@@ -1,2 +1,5 @@
 
-mod125.hs:7:5: Not in scope: data constructor `T'
+mod125.hs:7:5:
+    Not in scope: data constructor `T'
+    Perhaps you meant one of these:
+      `GT' (imported from Prelude), `LT' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/module/mod126.stderr b/testsuite/tests/ghc-regress/module/mod126.stderr
index 22243759ca..139a49c5d8 100644
--- a/testsuite/tests/ghc-regress/module/mod126.stderr
+++ b/testsuite/tests/ghc-regress/module/mod126.stderr
@@ -1,2 +1,5 @@
 
-mod126.hs:7:5: Not in scope: data constructor `T'
+mod126.hs:7:5:
+    Not in scope: data constructor `T'
+    Perhaps you meant one of these:
+      `GT' (imported from Prelude), `LT' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/module/mod127.stderr b/testsuite/tests/ghc-regress/module/mod127.stderr
index 5ffb1b71b6..4efd8270c9 100644
--- a/testsuite/tests/ghc-regress/module/mod127.stderr
+++ b/testsuite/tests/ghc-regress/module/mod127.stderr
@@ -1,2 +1,4 @@
 
-mod127.hs:6:6: Not in scope: type constructor or class `T'
+mod127.hs:6:6:
+    Not in scope: type constructor or class `T'
+    Perhaps you meant `T1' (imported from Mod127_A)
diff --git a/testsuite/tests/ghc-regress/module/mod130.stderr b/testsuite/tests/ghc-regress/module/mod130.stderr
index 27d3f8470e..3205babae0 100644
--- a/testsuite/tests/ghc-regress/module/mod130.stderr
+++ b/testsuite/tests/ghc-regress/module/mod130.stderr
@@ -1,2 +1,6 @@
 
-mod130.hs:7:5: Not in scope: `<'
+mod130.hs:7:5:
+    Not in scope: `<'
+    Perhaps you meant one of these:
+      `-' (imported from Prelude), `*' (imported from Prelude),
+      `.' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/module/mod134.stderr b/testsuite/tests/ghc-regress/module/mod134.stderr
index ca34584337..ed8382db63 100644
--- a/testsuite/tests/ghc-regress/module/mod134.stderr
+++ b/testsuite/tests/ghc-regress/module/mod134.stderr
@@ -1,2 +1,7 @@
 
-mod134.hs:6:19: Not in scope: `Prelude.head'
+mod134.hs:6:19:
+    Not in scope: `Prelude.head'
+    Perhaps you meant one of these:
+      `Prelude.read' (imported from Prelude),
+      `Prelude.reads' (imported from Prelude),
+      `Prelude.snd' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/module/mod136.stderr b/testsuite/tests/ghc-regress/module/mod136.stderr
index b9922fd653..242d20b3de 100644
--- a/testsuite/tests/ghc-regress/module/mod136.stderr
+++ b/testsuite/tests/ghc-regress/module/mod136.stderr
@@ -1,2 +1,6 @@
 
-mod136.hs:6:5: Not in scope: `zipWith5'
+mod136.hs:6:5:
+    Not in scope: `zipWith5'
+    Perhaps you meant one of these:
+      `zipWith' (imported from Mod136_A),
+      `zipWith3' (imported from Mod136_A)
diff --git a/testsuite/tests/ghc-regress/module/mod158.stderr b/testsuite/tests/ghc-regress/module/mod158.stderr
index 7f6c7d7e85..0599419100 100644
--- a/testsuite/tests/ghc-regress/module/mod158.stderr
+++ b/testsuite/tests/ghc-regress/module/mod158.stderr
@@ -1,3 +1,6 @@
 
-mod158.hs:12:5: Not in scope: data constructor `C'
+mod158.hs:12:5:
+    Not in scope: data constructor `C'
+    Perhaps you meant one of these:
+      `A' (imported from Mod157_D), `B' (imported from Mod157_D)
 exit(1)
diff --git a/testsuite/tests/ghc-regress/module/mod160.stderr b/testsuite/tests/ghc-regress/module/mod160.stderr
index 75bb3c16d6..c2dbd5647a 100644
--- a/testsuite/tests/ghc-regress/module/mod160.stderr
+++ b/testsuite/tests/ghc-regress/module/mod160.stderr
@@ -1,3 +1,6 @@
 
-mod160.hs:12:5: Not in scope: `m3'
+mod160.hs:12:5:
+    Not in scope: `m3'
+    Perhaps you meant one of these:
+      `m1' (imported from Mod159_D), `m2' (imported from Mod159_D)
 exit(1)
diff --git a/testsuite/tests/ghc-regress/module/mod25.stderr b/testsuite/tests/ghc-regress/module/mod25.stderr
index 49a15454aa..5133f1c169 100644
--- a/testsuite/tests/ghc-regress/module/mod25.stderr
+++ b/testsuite/tests/ghc-regress/module/mod25.stderr
@@ -1,2 +1,4 @@
 
-mod25.hs:3:16: Not in scope: type variable `b'
+mod25.hs:3:16:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 3)
diff --git a/testsuite/tests/ghc-regress/module/mod26.stderr b/testsuite/tests/ghc-regress/module/mod26.stderr
index 914f879d61..200a2c49a4 100644
--- a/testsuite/tests/ghc-regress/module/mod26.stderr
+++ b/testsuite/tests/ghc-regress/module/mod26.stderr
@@ -1,2 +1,4 @@
 
-mod26.hs:3:21: Not in scope: type variable `b'
+mod26.hs:3:21:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 3)
diff --git a/testsuite/tests/ghc-regress/module/mod62.stderr b/testsuite/tests/ghc-regress/module/mod62.stderr
index 68448ab9b1..d435dbd6b9 100644
--- a/testsuite/tests/ghc-regress/module/mod62.stderr
+++ b/testsuite/tests/ghc-regress/module/mod62.stderr
@@ -1,4 +1,6 @@
 
 mod62.hs:3:9: Qualified name in binding position: M.y
 
-mod62.hs:3:22: Not in scope: `M.y'
+mod62.hs:3:22:
+    Not in scope: `M.y'
+    Perhaps you meant `M.x' (line 3)
diff --git a/testsuite/tests/ghc-regress/module/mod72.stderr b/testsuite/tests/ghc-regress/module/mod72.stderr
index 7f047d8023..cc947b930b 100644
--- a/testsuite/tests/ghc-regress/module/mod72.stderr
+++ b/testsuite/tests/ghc-regress/module/mod72.stderr
@@ -1,2 +1,4 @@
 
-mod72.hs:3:7: Not in scope: `g'
+mod72.hs:3:7:
+    Not in scope: `g'
+    Perhaps you meant one of these: `x' (line 3), `f' (line 3)
diff --git a/testsuite/tests/ghc-regress/module/mod73.stderr b/testsuite/tests/ghc-regress/module/mod73.stderr
index 7a7ebbe385..c99c7ef1cb 100644
--- a/testsuite/tests/ghc-regress/module/mod73.stderr
+++ b/testsuite/tests/ghc-regress/module/mod73.stderr
@@ -1,2 +1,7 @@
 
-mod73.hs:3:7: Not in scope: `Prelude.g'
+mod73.hs:3:7:
+    Not in scope: `Prelude.g'
+    Perhaps you meant one of these:
+      `Prelude.id' (imported from Prelude),
+      `Prelude.gcd' (imported from Prelude),
+      `Prelude.log' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/parser/should_fail/readFail001.stderr b/testsuite/tests/ghc-regress/parser/should_fail/readFail001.stderr
index 5c11dcb375..5c2d03d136 100644
--- a/testsuite/tests/ghc-regress/parser/should_fail/readFail001.stderr
+++ b/testsuite/tests/ghc-regress/parser/should_fail/readFail001.stderr
@@ -2,13 +2,21 @@
 readFail001.hs:25:11:
     The fixity signature for `+#' lacks an accompanying binding
 
-readFail001.hs:38:48: Not in scope: type constructor or class `EqLeaf'
+readFail001.hs:38:48:
+    Not in scope: type constructor or class `EqLeaf'
 
-readFail001.hs:38:59: Not in scope: type constructor or class `EqLeaf'
+readFail001.hs:38:59:
+    Not in scope: type constructor or class `EqLeaf'
 
-readFail001.hs:87:11: Not in scope: `x'
+readFail001.hs:87:11:
+    Not in scope: `x'
+    Perhaps you meant one of these:
+      `a' (line 79), `b' (line 79), `c' (line 79)
 
-readFail001.hs:88:19: Not in scope: `x'
+readFail001.hs:88:19:
+    Not in scope: `x'
+    Perhaps you meant one of these:
+      `a' (line 79), `b' (line 79), `c' (line 79)
 
 readFail001.hs:94:19: Not in scope: `isSpace'
 
@@ -18,4 +26,5 @@ readFail001.hs:107:30: Not in scope: data constructor `Foo'
 
 readFail001.hs:107:42: Not in scope: data constructor `Bar'
 
-readFail001.hs:112:23: Not in scope: type constructor or class `Foo'
+readFail001.hs:112:23:
+    Not in scope: type constructor or class `Foo'
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/T2310.stderr b/testsuite/tests/ghc-regress/rename/should_fail/T2310.stderr
index d0e97fdff5..6500eef1fc 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/T2310.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/T2310.stderr
@@ -4,4 +4,7 @@ T2310.hs:5:22:
       Result signatures are no longer supported in pattern matches
     In a lambda abstraction: \ x :: a -> (x :: a)
 
-T2310.hs:5:39: Not in scope: `co'
+T2310.hs:5:39:
+    Not in scope: `co'
+    Perhaps you meant one of these:
+      `c' (line 5), `cos' (imported from Prelude)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail018.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail018.stderr
index 3bae3eb527..81b06ac3fc 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail018.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail018.stderr
@@ -1,8 +1,16 @@
 
-rnfail018.hs:12:37: Not in scope: type variable `a'
+rnfail018.hs:12:37:
+    Not in scope: type variable `a'
+    Perhaps you meant `b' (line 12)
 
-rnfail018.hs:12:42: Not in scope: type variable `m'
+rnfail018.hs:12:42:
+    Not in scope: type variable `m'
+    Perhaps you meant `b' (line 12)
 
-rnfail018.hs:12:47: Not in scope: type variable `m'
+rnfail018.hs:12:47:
+    Not in scope: type variable `m'
+    Perhaps you meant `b' (line 12)
 
-rnfail018.hs:12:49: Not in scope: type variable `a'
+rnfail018.hs:12:49:
+    Not in scope: type variable `a'
+    Perhaps you meant `b' (line 12)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail022.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail022.stderr
index 29df5455f3..b733e836e3 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail022.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail022.stderr
@@ -1,2 +1,4 @@
 
-rnfail022.hs:8:5: Not in scope: `intersperse'
+rnfail022.hs:8:5:
+    Not in scope: `intersperse'
+    Perhaps you meant `L.intersperse' (imported from List)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail032.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail032.stderr
index 5007b8ed38..374d183bfc 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail032.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail032.stderr
@@ -1,2 +1,4 @@
 
-rnfail032.hs:2:21: Not in scope: `List.map'
+rnfail032.hs:2:21:
+    Not in scope: `List.map'
+    Perhaps you meant `List.zip' (imported from List)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail033.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail033.stderr
index ac28110648..8aa32f8025 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail033.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail033.stderr
@@ -1,2 +1,4 @@
 
-rnfail033.hs:2:21: Not in scope: `List.map'
+rnfail033.hs:2:21:
+    Not in scope: `List.map'
+    Perhaps you meant `List.zip' (imported from List)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail034.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail034.stderr
index 4aab3c501a..2ec0a3b8e5 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail034.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail034.stderr
@@ -1,4 +1,6 @@
 
 rnfail034.hs:4:11: Qualified name in binding position: M.y
 
-rnfail034.hs:4:26: Not in scope: `M.y'
+rnfail034.hs:4:26:
+    Not in scope: `M.y'
+    Perhaps you meant `M.g' (line 4)
diff --git a/testsuite/tests/ghc-regress/rename/should_fail/rnfail035.stderr b/testsuite/tests/ghc-regress/rename/should_fail/rnfail035.stderr
index 83eb2d85e3..e62c20552f 100644
--- a/testsuite/tests/ghc-regress/rename/should_fail/rnfail035.stderr
+++ b/testsuite/tests/ghc-regress/rename/should_fail/rnfail035.stderr
@@ -1,2 +1,4 @@
 
-rnfail035.hs:2:21: Not in scope: type constructor or class `C'
+rnfail035.hs:2:21:
+    Not in scope: type constructor or class `C'
+    Perhaps you meant `T' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail011.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail011.stderr
index f41e3a67ce..916b160e8a 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail011.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail011.stderr
@@ -1,2 +1,4 @@
 
-tcfail011.hs:3:25: Not in scope: `y'
+tcfail011.hs:3:25:
+    Not in scope: `y'
+    Perhaps you meant one of these: `x' (line 3), `z' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail048.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail048.stderr
index 569b85f915..8f65f0fd04 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail048.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail048.stderr
@@ -1,2 +1,4 @@
 
-tcfail048.hs:3:7: Not in scope: type constructor or class `B'
+tcfail048.hs:3:7:
+    Not in scope: type constructor or class `B'
+    Perhaps you meant `C' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail049.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail049.stderr
index 750a65bc3c..8335f130ac 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail049.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail049.stderr
@@ -1,2 +1,4 @@
 
-tcfail049.hs:3:7: Not in scope: `g'
+tcfail049.hs:3:7:
+    Not in scope: `g'
+    Perhaps you meant one of these: `x' (line 3), `f' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail052.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail052.stderr
index 9ffa31c227..1eaa34dc5e 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail052.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail052.stderr
@@ -1,2 +1,4 @@
 
-tcfail052.hs:3:16: Not in scope: type variable `c'
+tcfail052.hs:3:16:
+    Not in scope: type variable `c'
+    Perhaps you meant `a' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail053.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail053.stderr
index 9889c3f0f6..e792c7e37e 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail053.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail053.stderr
@@ -1,2 +1,4 @@
 
-tcfail053.hs:3:12: Not in scope: type constructor or class `A'
+tcfail053.hs:3:12:
+    Not in scope: type constructor or class `A'
+    Perhaps you meant `B' (line 3)
diff --git a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail061.stderr b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail061.stderr
index a047863e9b..5afe1509f0 100644
--- a/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail061.stderr
+++ b/testsuite/tests/ghc-regress/typecheck/should_fail/tcfail061.stderr
@@ -1,8 +1,16 @@
 
-tcfail061.hs:5:17: Not in scope: type variable `b'
+tcfail061.hs:5:17:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 5)
 
-tcfail061.hs:5:19: Not in scope: type variable `b'
+tcfail061.hs:5:19:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 5)
 
-tcfail061.hs:11:22: Not in scope: type variable `b'
+tcfail061.hs:11:22:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 11)
 
-tcfail061.hs:11:24: Not in scope: type variable `b'
+tcfail061.hs:11:24:
+    Not in scope: type variable `b'
+    Perhaps you meant `a' (line 11)