Why is `man` outputing to stdout instead of $PAGER (less)?

Question

When I run man [program], the man page text is output on the terminal (a la cat, without a pager that provides interactivity) instead of opening the man page file in less (so you can scroll, search, etc.):

➜ man git commit
GIT-COMMIT(1)                   Git Manual                  GIT-COMMIT(1)

NAME
       git-commit - Record changes to the repository

SYNOPSIS
[...the rest of the man page]

I've verified that echo $PAGER returns less. Running man -D -P less [program] still outputs to the terminal "like cat does", without providing the ability to scroll or search etc., like less usually does.

Using the debug flag -d, man says "using /usr/bin/less as pager". I'm at a loss for what is happening.

Other useful information:

➜ env | grep LESS       
LESS=-R -M
LESS_TERMCAP_mb=
LESS_TERMCAP_md=
LESS_TERMCAP_me=
LESS_TERMCAP_so=
LESS_TERMCAP_se=
LESS_TERMCAP_us=
LESS_TERMCAP_ue=
➜ echo $TERM     
xterm-256color

I do get an error for only one program. I don't believe it is directly relevant, but see this GH issue for details on that. tl;dr, the error that appears is troff: <standard input>:1: name expected (got '\ '): treated as missing

This is also cross posted to the Manjaro forums here.

Update:

Issue is with zpm-zsh/colorize. I thought doing \man would ignore the function, but \ only ignores aliases. Removing this plugin solves the issue, but I'd like to understand why.

Answer 1

The problem I was running was a namespace matching issue with env.

oh-my-zsh's colored-man-pages uses env when setting up variables:

function colored() {
    env \
        LESS_TERMCAP_mb=$(printf "\e[1;31m") \
        LESS_TERMCAP_md=$(printf "\e[1;31m") \
        LESS_TERMCAP_me=$(printf "\e[0m") \
        LESS_TERMCAP_se=$(printf "\e[0m") \
        LESS_TERMCAP_so=$(printf "\e[1;44;33m") \
        LESS_TERMCAP_ue=$(printf "\e[0m") \
        LESS_TERMCAP_us=$(printf "\e[1;32m") \
        PAGER="${commands[less]:-$PAGER}" \
        _NROFF_U=1 \
        PATH="$HOME/bin:$PATH" \
            "$@"
}

function man() {
    colored man "$@"
}

I also use another plugin, zpm-zsh/colorize which routes env through grv (general colourizer) through as a separate function called env:

function env () {
    =grc --colour=auto env "$@"
}

For whatever reason, grc does something that man doesn't like.

Solution:

1) Don't redefine env through grc using a globally defined function

2) Ensure that env is not an alias/function by using command

function colored() {
    command env \
        LESS_TERMCAP_mb=$(printf "\e[1;31m") \
[....]
}

function man() {
    colored man "$@"
}