installShellFiles: rewrite functions

- Use FUNCNAME to track the name of function being called
- use long options for install commands
- use nix*Log functions for logging, instead of custom echoes
- remove silent error construction `|| return`

pkgs/by-name/in/installShellFiles/setup-hook.sh

···
 installManPage() {
     local path
     for path in "$@"; do
-        if (( "${NIX_DEBUG:-0}" >= 1 )); then
-            echo "installManPage: installing $path"
-        fi
         if test -z "$path"; then
-            echo "installManPage: error: path cannot be empty" >&2
+            nixErrorLog "${FUNCNAME[0]}: path cannot be empty"
             return 1
         fi
+        nixInfoLog "${FUNCNAME[0]}: installing $path"
         local basename
         basename=$(stripHash "$path") # use stripHash in case it's a nix store path
         local trimmed=${basename%.gz} # don't get fooled by compressed manpages
         local suffix=${trimmed##*.}
         if test -z "$suffix" -o "$suffix" = "$trimmed"; then
-            echo "installManPage: error: path missing manpage section suffix: $path" >&2
+            nixErrorLog "${FUNCNAME[0]}: path missing manpage section suffix: $path"
             return 1
         fi
         local outRoot
···
         else
             outRoot=${!outputMan:?}
         fi
-        install -Dm644 -T "$path" "${outRoot}/share/man/man$suffix/$basename" || return
+        local outPath="${outRoot}/share/man/man$suffix/$basename"
+        install -D --mode=644 --no-target-directory "$path" "$outPath"
     done
 }
 
···
             --name)
                 name=$1
                 shift || {
-                    echo 'installShellCompletion: error: --name flag expected an argument' >&2
+                    nixErrorLog "${FUNCNAME[0]}: --name flag expected an argument"
                     return 1
                 }
                 continue;;
···
             --cmd)
                 cmdname=$1
                 shift || {
-                    echo 'installShellCompletion: error: --cmd flag expected an argument' >&2
+                    nixErrorLog "${FUNCNAME[0]}: --cmd flag expected an argument"
                     return 1
                 }
                 continue;;
···
                 cmdname=${arg#--cmd=}
                 continue;;
             --?*)
-                echo "installShellCompletion: warning: unknown flag ${arg%%=*}" >&2
+                nixWarnLog "${FUNCNAME[0]}: unknown flag ${arg%%=*}"
                 retval=2
                 continue;;
             --)
···
                 continue;;
             esac
         fi
-        if (( "${NIX_DEBUG:-0}" >= 1 )); then
-            echo "installShellCompletion: installing $arg${name:+ as $name}"
-        fi
+        nixInfoLog "${FUNCNAME[0]}: installing $arg${name:+ as $name}"
         # if we get here, this is a path or named pipe
         # Identify shell and output name
         local curShell=$shell
         local outName=''
         if [[ -z "$arg" ]]; then
-            echo "installShellCompletion: error: empty path is not allowed" >&2
+            nixErrorLog "${FUNCNAME[0]}: empty path is not allowed"
             return 1
         elif [[ -p "$arg" ]]; then
             # this is a named fd or fifo
             if [[ -z "$curShell" ]]; then
-                echo "installShellCompletion: error: named pipe requires one of --bash, --fish, or --zsh" >&2
+                nixErrorLog "${FUNCNAME[0]}: named pipe requires one of --bash, --fish, or --zsh"
                 return 1
             elif [[ -z "$name" && -z "$cmdname" ]]; then
-                echo "installShellCompletion: error: named pipe requires one of --cmd or --name" >&2
+                nixErrorLog "${FUNCNAME[0]}: named pipe requires one of --cmd or --name"
                 return 1
             fi
         else
···
                 *)
                     if [[ "$argbase" = _* && "$argbase" != *.* ]]; then
                         # probably zsh
-                        echo "installShellCompletion: warning: assuming path \`$arg' is zsh; please specify with --zsh" >&2
+                        nixWarnLog "${FUNCNAME[0]}: assuming path \`$arg' is zsh; please specify with --zsh"
                         curShell=zsh
                     else
-                        echo "installShellCompletion: warning: unknown shell for path: $arg" >&2
+                        nixWarnLog "${FUNCNAME[0]}: unknown shell for path: $arg" >&2
                         retval=2
                         continue
                     fi;;
···
             zsh) outName=_$cmdname;;
             *)
                 # Our list of shells is out of sync with the flags we accept or extensions we detect.
-                echo 'installShellCompletion: internal error' >&2
+                nixErrorLog "${FUNCNAME[0]}: internal: shell $curShell not recognized"
                 return 1;;
             esac
         fi
···
             fi;;
         *)
             # Our list of shells is out of sync with the flags we accept or extensions we detect.
-            echo 'installShellCompletion: internal error' >&2
+            nixErrorLog "${FUNCNAME[0]}: internal: shell $curShell not recognized"
             return 1;;
         esac
         # Install file
···
             mkdir -p "$outDir" \
             && cat "$arg" > "$outPath"
         else
-            install -Dm644 -T "$arg" "$outPath"
-        fi || return
+            install -D --mode=644 --no-target-directory "$arg" "$outPath"
+        fi
 
         if [ ! -s "$outPath" ]; then
-            echo "installShellCompletion: error: installed shell completion file \`$outPath' does not exist or has zero size" >&2
+            nixErrorLog "${FUNCNAME[0]}: installed shell completion file \`$outPath' does not exist or has zero size"
             return 1
         fi
         # Clear the per-path flags
         name=
     done
     if [[ -n "$name" ]]; then
-        echo 'installShellCompletion: error: --name flag given with no path' >&2
+        nixErrorLog "${FUNCNAME[0]}: --name flag given with no path" >&2
         return 1
     fi
     return $retval
···
 installBin() {
     local path
     for path in "$@"; do
-        if (( "${NIX_DEBUG:-0}" >= 1 )); then
-            echo "installBin: installing $path"
-        fi
         if test -z "$path"; then
-            echo "installBin: error: path cannot be empty" >&2
+            nixErrorLog "${FUNCNAME[0]}: path cannot be empty"
             return 1
         fi
+        nixInfoLog "${FUNCNAME[0]}: installing $path"
+
         local basename
         # use stripHash in case it's a nix store path
         basename=$(stripHash "$path")
···
         local outRoot
         outRoot=${!outputBin:?}
 
-        install -D --mode=755 --no-target-directory "$path" "${outRoot}/bin/$basename" || return
+        local outPath="${outRoot}/bin/$basename"
+        install -D --mode=755 --no-target-directory "$path" "${outRoot}/bin/$basename"
     done
 }