How to add parens around text

Question

How can I use sed to replace text and also append to end of line for the match in question?

I have a sed file which is doing many substitutions.

One of them changes ~= to match( using /=\~/ s/=\~/match( /

When doing this, I also want to add a ")" (space + end paren) at the end of the line in question (that met the original match)

I tried this with this sed line:

/=\~/ s/=\~/match(/ s/$/ )/

but I got our favorite sed: -e expression #1, char 77: unknown option tos'`
(line 77 'cos this sed has lots of other stuff (omitted)).

How can I append a ) for these lines? Can I do it within this match or do I need another line for it? I would like it to only be for these matches or I might end up adding an extra ) for "existing" match() expressions.

fwiw the full sed is..

  sed -i 's/\.should/)\.to/
          /\.to ==/s/==/eq/
          /=\~/ s/=\~/match(/ s/$/ )/  <--- line in question
          /[^}.to|end.to]\.to[[:space:]]/ s/\(\S\)/expect(\1/
          /[^}.to|end.to]\.to_not[[:space:]]/ s/\(\S\)/expect(\1/
          s/[^}.to|end.to].to[[:space:]]/).to /
          s/to_receive/to receive/
          s/to_not_receive/to_not receive/' ../_spec_seded/"$file"

Answer 1

Try this:

sed -r "s/=~(.*)$/match(\1)/" <filename>

Also, the error that you are getting is because sed interprets /=\~/ as a filter for the line that the operation should be performed, s/=\~/match(/ as the operation and s/$/ )/ as a flag for the operation, in this case you need to use a group and separate the expressions with a new line:

sed -re "/=\~/ {
  s/=\~/match(/
  s/$/ )/
}" <filename>

Here is the relevant documentation about the command block {} from info sed

`{ COMMANDS }'
 A group of commands may be enclosed between `{' and `}' characters.
 This is particularly useful when you want a group of commands to
 be triggered by a single address (or address-range) match.