shell - zsh function wrapping grep output only returns a few lines -

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i'm trying create small zsh function allows me grep history - hgrep test should return every command i've typed containts test.

on machine returns 6 results. when type history | grep test lot more results. gives?

hgrep (){      history | grep $1 }

the output - complete!

➜  ~ hgrep test  7887  mkd test  7889  rm -r test  7894  hgrep test  7896  history | grep test

this incomplete output. also, notice first results much earlier

➜  ~ history | grep test   252  cp mgroup /test   254  cp mgroup /test   322  vi test.js   324  node test.js   325  vi test.js ...

after poking around appears difference in behavior related when .zshrc sourced. on new terminal see unwanted behavior. if source ~/.zshrc works.

however, i'm still confused why happen.

it seems history command aliased else (for example fc -l 1) after definition of hgrep function.

so, put hgrep function definition after alias setups. or, define hgrep function (and functions) not affected aliases, shell options etc.

tl;dr

the command history lists last 16 events default.

history

same fc -l.
[…]
fc -l ... [ first [ last ] ]

if first not specified, set -1 (the recent event), or -16 if -l flag given.

-- zshbuiltins(1) shell builtin commands fc, history

and aliases checked , expanded @ read time.

every eligible word in shell input checked see if there alias defined it. if so, replaced text of alias if in command position
[…]
aliases expanded when code read in; entire line read in 1 go

-- zshmisc(1) aliasing

it seems thehgrep function uses shell-builtin command history shows few events , results may differ using history (which alias else) interactively.

the hgrep function redefined source ~/.zshrc, history in function expanded/replaced alias @ point. check resulting function issuing below command:

% functions hgrep hgrep () { … (hgrep function's definition shown)

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