First of all, as a basic concept of git diff, the basic behavior of “git diff” is “display of changes made in the working tree”.
Then, if you do not specify the comparison source, you can specify “comparison source” as an argument, but by default, the difference when compared with “index” → ”working tree” with “index” as the comparison source and it will display.
[vagrant@localhost tests]$ git diff
diff –git a/sample.txt b/sample.txt
deleted file mode 100644
index 106287c..0000000
— a/sample.txt
+++ /dev/null
@@ -1 +0,0 @@
-Hello Git!
diff –git a/tests/test b/tests/test
— a/tests/test
+++ b/tests/test
@@ -1 +1 @@
-Subproject commit 180cf3fcce48d905ede71a57ed0bd3973e1f90c8
+Subproject commit 180cf3fcce48d905ede71a57ed0bd3973e1f90c8-dirty
[vagrant@localhost tests]$ git diff –name-only
sample.txt
tests/test
あれ？
[vagrant@localhost test]$ git diff –name-only
addfile.txt
[vagrant@localhost test]$
OK、理解した。
