sed mac insert tab and text at specific line

Question

I'm trying to use sed to insert a tab followed by a string with quotes (json) followed by a newline on mac on the second line. So far I've got

sed -i '.json' "2i\\
\"$(printf '\t') \"1.0.1\": \"1.0.1.zip\",\\
    " dummy.txt

and that outputs

"        "1.0.1": "1.0.1.zip",

and then when I try to remove the \"

sed -i '.json' "2i\\
$(printf '\t') \"1.0.1\": \"1.0.1.zip\",\\
    " dummy.txt

No tab is there. am i missing something here to get the tab?

Edit: I tried this

version=5.5.1

sed -i '' "2i\\
echo -e [\\t] \"1.0.1\": \"1.0.1.zip\",\\
    " dummy.txt

and the output of my dummy.txt file is

echo -e [t] "1.0.1": "1.0.1.zip",

No tab is present.

Answer 1

The problem is the single quotes. The shell interprets single quotes as "pass this on verbatim, without interpreting any special characters". You need to replace them with double quotes and escape the double quotes inside the parameter. Something like this:

sed -i "2i\\
\"1.0.1\": \"1.0.1.zip\",
   " file.json

For your original question, inserting a tab with sed, this works (2i will insert at line 2, where the first line of the file is 1). If you want to add a tab character in the command line (or in vim), press Ctrl+Q-<Tab> to tell it that the tab character is literal and not to be interpreted by the editor/shell. In the case of other editors, look in the editor documentation to see how to enter a literal tab.

The example would be:

sed -i.json "2i\\
\"1.0.1\": \"1.0.1.zip\",
<Ctrl-Q><Tab>" file.json

where the <Ctrl-Q><Tab> sequence means pressing those specific keys. This will depend on the editor that you are using. In the comments you mention that you are using VS Code, so instead of the <Ctrl+Q><Tab> trick you might want to use one of the options given in the answers to this question: https://stackoverflow.com/questions/45566785/vscode-insert-tab-character-manually

Note also that there is no space between -i and .json.