diff - 输出行号

Question

我想使用 cli 工具进行文件比较，并且在输出行之前需要行号，这有助于我可以跳转到行差异，因为我使用的工具可以了解跳转的位置，如果行是这样开始的 :line-number: regular line contents

所以我尝试了diff，阅读文档似乎是可能的：

  -D, --ifdef=NAME                output merged file with `#ifdef NAME' diffs
      --GTYPE-group-format=GFMT   format GTYPE input groups with GFMT
      --line-format=LFMT          format all input lines with LFMT
      --LTYPE-line-format=LFMT    format LTYPE input lines with LFMT
    These format options provide fine-grained control over the output
      of diff, generalizing -D/--ifdef.
    LTYPE is `old', `new', or `unchanged'.  GTYPE is LTYPE or `changed'.
    GFMT (only) may contain:
      %<  lines from FILE1
      %>  lines from FILE2
      %=  lines common to FILE1 and FILE2
      %[-][WIDTH][.[PREC]]{doxX}LETTER  printf-style spec for LETTER
        LETTERs are as follows for new group, lower case for old group:
          F  first line number
          L  last line number
          N  number of lines = L-F+1
          E  F-1
          M  L+1
      %(A=B?T:E)  if A equals B then T else E
    LFMT (only) may contain:
      %L  contents of line
      %l  contents of line, excluding any trailing newline
      %[-][WIDTH][.[PREC]]{doxX}n  printf-style spec for input line number
    Both GFMT and LFMT may contain:
      %%  %
      %c'C'  the single character C
      %c'\OOO'  the character with octal code OOO
      C    the character C (other characters represent themselves)

但是没有关于这个复杂开关的例子或解释。

是否有可能从 获得这样的输出diff？如果是这样怎么办？

Answer 1

对的，这是可能的。使用这些选项时，默认值只是打印出每一行。这是非常冗长的，而不是你想要的。

diff --unchanged-line-format=""

将消除未更改的行，因此现在只生成旧行和新行。

diff --unchanged-line-format="" --new-line-format=":%dn: %L"

现在将显示以:<linenumber>:空格为前缀的新行，但仍打印旧行。假设你想消除它们，

diff --unchanged-line-format="" --old-line-format="" --new-line-format=":%dn: %L"

如果您希望打印旧行而不是新行，请交换它们。