file-contents-sorter doesn't use consistent order with --ignore-case option

[alexdewar]

I'm trying to use file-contents-sorter to keep a dictionary file sorted, ignoring case. The hook runs fine and updates the file, but when I attempt to commit the changes, it resorts the file again, moving around some entries which differ only in case. If I try to commit those changes, the process repeats.

[asottile]

works fine for me? please show an actual reproduction

[007]

If lines differ only in case and you specify case-insensitive sorting the results are non-idempotent.

$ cat wtf.wtf
AAA
bbb
BbB
ccc

Then file-contents-sorter with --ignore-case on that file, run 10 times in a row:

$ for x in $(seq 10); do pre-commit run --all;git diff wtf.wtf;done

file contents sorter.....................................................Passed
file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc
file contents sorter.....................................................Passed
diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc
file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc
file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc
file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

file contents sorter.....................................................Failed
- hook id: file-contents-sorter
- exit code: 1
- files were modified by this hook

Sorting wtf.wtf

diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc
file contents sorter.....................................................Passed
diff --git i/wtf.wtf w/wtf.wtf
index 76baeb04f9029d8c..ce2c79e355ff977d 100644
--- i/wtf.wtf
+++ w/wtf.wtf
@@ -1,4 +1,4 @@
 AAA
-bbb
 BbB
+bbb
 ccc

[asottile]

then that's a dupe of #794