在命令的git 文档中blame它说（强调我的）：
C[<数字>]
除了 -M 之外，检测从在同一提交中修改的其他文件移动或复制的行。当您重新组织程序并跨文件移动代码时，这很有用。当此选项被给出两次时，该命令还会在创建文件的提交中查找其他文件的副本。当此选项被给出 3 次时，该命令还会在任何提交中查找来自其他文件的副本。[...]
首先，“提交中创建文件的其他文件”是什么意思？它是否查找在添加文件的同一提交中修改的文件？或者它是否查找仅存在于添加文件的提交树中的所有文件？
我尝试了一个示例，在该示例中，我在同一个提交中创建了一个非空文件（named source）和一个空文件（name ）。dest在接下来的提交中，我做了一些不相关的事情。在第三次也是最后一次提交中，我从sourceto复制了几行dest。结果如下所示（内容比较大，尽量不要混淆git的算法，对此我深表歉意）：
$ git init
$ cat source
--incremental Show blame entries as we find them, incrementally
-b Show blank SHA-1 for boundary commits (Default: off)
--root Do not treat root commits as boundaries (Default: off)
--show-stats Show work cost statistics
--score-debug Show output score for blame entries
-f, --show-name Show original filename (Default: auto)
-n, --show-number Show original linenumber (Default: off)
-p, --porcelain Show in a format designed for machine consumption
--line-porcelain Show porcelain format with per-line commit information
-c Use the same output mode as git-annotate (Default: off)
-t Show raw timestamp (Default: off)
-l Show long commit SHA1 (Default: off)
-s Suppress author name and timestamp (Default: off)
-e, --show-email Show author email instead of name (Default: off)
-w Ignore whitespace differences
--minimal Spend extra cycles to find better match
-S <file> Use revisions from <file> instead of calling git-rev-list
--contents <file> Use <file>'s contents as the final image
-C[<score>] Find line copies within and across files
-M[<score>] Find line movements within and across files
-L <n,m> Process only line range n,m, counting from 1
--abbrev[=<n>] use <n> digits to display SHA-1s
$ cat dest
first initial line in dest
second initial line in dest
$ git add source dest
$ git commit -m "Add source and dest files"
$ touch new-file
$ git add new-file
$ git commit -m "Add irrelevant file"
$ (copy some lines from source to dest)
$ cat dest
first initial line in dest
--show-stats Show work cost statistics
--score-debug Show output score for blame entries
-f, --show-name Show original filename (Default: auto)
-n, --show-number Show original linenumber (Default: off)
-p, --porcelain Show in a format designed for machine consumption
--line-porcelain Show porcelain format with per-line commit information
-c Use the same output mode as git-annotate (Default: off)
-t Show raw timestamp (Default: off)
-l Show long commit SHA1 (Default: off)
-s Suppress author name and timestamp (Default: off)
-e, --show-email Show author email instead of name (Default: off)
-w Ignore whitespace differences
--minimal Spend extra cycles to find better match
-S <file> Use revisions from <file> instead of calling git-rev-list
--contents <file> Use <file>'s contents as the final image
second initial line in dest
$ git add dest
$ git commit -m "Copy lines from source to dest"
$ git log --pretty=oneline
6b0f18daaf83ec83d3f53b4a43f4188de3ce87e6 copy lines from source to dest
f1d66ad3dacb8e589747ed02b42d9135081b3704 Add irrelevant file
2b8275dc73ffd88d7adb6f90a2050ef14088019a Add source and dest files
$ git blame dest
^2b8275d - 1) first initial line in dest
6b0f18da - 2) --show-stats Show work cost statistics
6b0f18da - 3) --score-debug Show output score for blame entries
6b0f18da - 4) -f, --show-name Show original filename (Default: auto)
6b0f18da - 5) -n, --show-number Show original linenumber (Default: off)
6b0f18da - 6) -p, --porcelain Show in a format designed for machine consumption
6b0f18da - 7) --line-porcelain Show porcelain format with per-line commit information
6b0f18da - 8) -c Use the same output mode as git-annotate (Default: off)
6b0f18da - 9) -t Show raw timestamp (Default: off)
6b0f18da - 10) -l Show long commit SHA1 (Default: off)
6b0f18da - 11) -s Suppress author name and timestamp (Default: off)
6b0f18da - 12) -e, --show-email Show author email instead of name (Default: off)
6b0f18da - 13) -w Ignore whitespace differences
6b0f18da - 14) --minimal Spend extra cycles to find better match
6b0f18da - 15) -S <file> Use revisions from <file> instead of calling git-rev-list
6b0f18da - 16) --contents <file> Use <file>'s contents as the final image
^2b8275d - 17) second initial line in dest
$ git blame -C dest
^2b8275d - 1) first initial line in dest
6b0f18da - 2) --show-stats Show work cost statistics
6b0f18da - 3) --score-debug Show output score for blame entries
6b0f18da - 4) -f, --show-name Show original filename (Default: auto)
6b0f18da - 5) -n, --show-number Show original linenumber (Default: off)
6b0f18da - 6) -p, --porcelain Show in a format designed for machine consumption
6b0f18da - 7) --line-porcelain Show porcelain format with per-line commit information
6b0f18da - 8) -c Use the same output mode as git-annotate (Default: off)
6b0f18da - 9) -t Show raw timestamp (Default: off)
6b0f18da - 10) -l Show long commit SHA1 (Default: off)
6b0f18da - 11) -s Suppress author name and timestamp (Default: off)
6b0f18da - 12) -e, --show-email Show author email instead of name (Default: off)
6b0f18da - 13) -w Ignore whitespace differences
6b0f18da - 14) --minimal Spend extra cycles to find better match
6b0f18da - 15) -S <file> Use revisions from <file> instead of calling git-rev-list
6b0f18da - 16) --contents <file> Use <file>'s contents as the final image
^2b8275d - 17) second initial line in dest
$ git blame -C -C dest
^2b8275d - 1) first initial line in dest
6b0f18da - 2) --show-stats Show work cost statistics
6b0f18da - 3) --score-debug Show output score for blame entries
6b0f18da - 4) -f, --show-name Show original filename (Default: auto)
6b0f18da - 5) -n, --show-number Show original linenumber (Default: off)
6b0f18da - 6) -p, --porcelain Show in a format designed for machine consumption
6b0f18da - 7) --line-porcelain Show porcelain format with per-line commit information
6b0f18da - 8) -c Use the same output mode as git-annotate (Default: off)
6b0f18da - 9) -t Show raw timestamp (Default: off)
6b0f18da - 10) -l Show long commit SHA1 (Default: off)
6b0f18da - 11) -s Suppress author name and timestamp (Default: off)
6b0f18da - 12) -e, --show-email Show author email instead of name (Default: off)
6b0f18da - 13) -w Ignore whitespace differences
6b0f18da - 14) --minimal Spend extra cycles to find better match
6b0f18da - 15) -S <file> Use revisions from <file> instead of calling git-rev-list
6b0f18da - 16) --contents <file> Use <file>'s contents as the final image
^2b8275d - 17) second initial line in dest
$ git blame -C -C -C dest
^2b8275d dest - 1) first initial line in dest
^2b8275d source - 2) --show-stats Show work cost statistics
^2b8275d source - 3) --score-debug Show output score for blame entries
^2b8275d source - 4) -f, --show-name Show original filename (Default: auto)
^2b8275d source - 5) -n, --show-number Show original linenumber (Default: off)
^2b8275d source - 6) -p, --porcelain Show in a format designed for machine consumption
^2b8275d source - 7) --line-porcelain Show porcelain format with per-line commit information
^2b8275d source - 8) -c Use the same output mode as git-annotate (Default: off)
^2b8275d source - 9) -t Show raw timestamp (Default: off)
^2b8275d source - 10) -l Show long commit SHA1 (Default: off)
^2b8275d source - 11) -s Suppress author name and timestamp (Default: off)
^2b8275d source - 12) -e, --show-email Show author email instead of name (Default: off)
^2b8275d source - 13) -w Ignore whitespace differences
^2b8275d source - 14) --minimal Spend extra cycles to find better match
^2b8275d source - 15) -S <file> Use revisions from <file> instead of calling git-rev-list
^2b8275d source - 16) --contents <file> Use <file>'s contents as the final image
^2b8275d dest - 17) second initial line in dest
可以看出，git blame -C -C dest没有意识到中的新行dest来自source，该文件是使用与dest. 但是，git blame -C -C -C dest给出了预期的输出。
难道我做错了什么？
谢谢你。
编辑：
我相信
[...]当这个选项被给出两次时，该命令还会在创建文件的提交中查找来自其他文件的副本。[...]
意味着它将查找仅git在实际创建文件的提交中发生的行副本（来自其他文件），而不是它将查找来自其他文件（存在于创建文件的提交中的文件）的行副本。这个误会和我的第一个问题有关。