Merge pull request #5928 from sboosali/master

fix « cabal »'s bash-completion (see issue #5927)

cabal-install/bash-completion/cabal

@@ -1,45 +1,170 @@
+#!/bin/bash
+
+### -*- mode: shell-script; -*-
+
+##################################################
+
 # cabal command line completion
+#
 # Copyright 2007-2008 "Lennart Kolmodin" <[email protected]>
-#                     "Duncan Coutts"     <[email protected]>
+#                     "Duncan Coutts"    <[email protected]>
+#                     "Sam Boosalis"     <[email protected]>
+#
+
+##################################################
+
+# List project-specific (/ internal) packages:
+#
+#
+
+function _cabal_list_packages ()
+(
+    shopt -s nullglob
+
+    local CabalFiles
+    CabalFiles=( ./*.cabal ./*/*.cabal ./*/*/*.cabal )
+
+    for FILE in "${CabalFiles[@]}"
+    do
+
+        BASENAME=$(basename "$FILE")
+        PACKAGE="${BASENAME%.cabal}"
+
+        echo "$PACKAGE"
+
+    done | sort | uniq
+)
+
+# NOTES
+#
+# [1] « "${string%suffix}" » strips « suffix » from « string »,
+#     in pure Bash.
+#
+# [2] « done | sort | uniq » removes duplicates from the output of the for-loop.
 #
 
+##################################################
+
+
 # List cabal targets by type, pass:
-#   - test-suite for test suites
-#   - benchmark for benchmarks
-#   - executable for executables
-#   - executable|test-suite|benchmark for the three
-_cabal_list()
+#
+#   - ‹test-suite› for test suites
+#   - ‹benchmark› for benchmarks
+#   - ‹executable› for executables
+#   - ‹library› for internal libraries
+#   - ‹foreign-library› for foreign libraries
+#   - nothing for all components.
+#
+
+function _cabal_list_targets ()
+(
+    shopt -s nullglob
+
+    # ^ NOTE « _cabal_list_targets » must be a subshell to temporarily enable « nullglob ».
+    #        hence, « function _ () ( ... ) » over « function _ () { ... } ».
+    #        without « nullglob », if a glob-pattern fails, it becomes a literal
+    #        (i.e. the string with an asterix, rather than an empty string).
+
+    CabalComponent=${1:-library|executable|test-suite|benchmark|foreign-library}
+
+    local CabalFiles
+    CabalFiles=( ./*.cabal ./*/*.cabal ./*/*/*.cabal )
+
+    for FILE in "${CabalFiles[@]}"
+    do
+
+        grep -E -i "^[[:space:]]*($CabalComponent)[[:space:]]" "$FILE" 2>/dev/null | sed -e "s/.* \([^ ]*\).*/\1/" | sed -e '/^$/d'
+
+    done | sort | uniq
+)
+
+# NOTES
+#
+# [1] in « sed '/^$/d' »:
+#
+#     * « d » is the sed command to delete a line.
+#     * « ^$ » is a regular expression matching only a blank line
+#       (i.e. a line start followed by a line end).
+#
+#     dropping blank lines is necessary to ignore public « library » stanzas,
+#     while still matching private « library _ » stanzas.
+#
+# [2]
+#
+
+#TODO# rm duplicate components and qualify with « PACKAGE: » (from basename):
+#
+# $ .. | sort | uniq
+
+##################################################
+
+# List known (/ external) packages:
+#
+function _cabal_list_external_packages ()
 {
-    for f in ./*.cabal; do
-        grep -Ei "^[[:space:]]*($1)[[:space:]]" "$f" |
-        sed -e "s/.* \([^ ]*\).*/\1/"
-    done
+
+    cabal list --simple-output
+
 }
 
+# NOTES
+#
+# [1] this is slow.
+#     e.g. « cabal list --simple-output » output ~100,000 lines,
+#          given multiple versions and different « repository »'s
+#          (which took several seconds to print out).
+#
+# [2]
+#
+
+##################################################
+
 # List possible targets depending on the command supplied as parameter.  The
 # ideal option would be to implement this via --list-options on cabal directly.
 # This is a temporary workaround.
-_cabal_targets()
+
+function _cabal_targets ()
+
 {
-    # If command ($*) contains build, repl, test or bench completes with
-    # targets of according type.
-    local comp
-    for comp in "$@"; do
-        [ "$comp" == new-build ] && _cabal_list "executable|test-suite|benchmark" && break
-        [ "$comp" == build     ] && _cabal_list "executable|test-suite|benchmark" && break
-        [ "$comp" == repl      ] && _cabal_list "executable|test-suite|benchmark" && break
-        [ "$comp" == run       ] && _cabal_list "executable"                      && break
-        [ "$comp" == test      ] && _cabal_list            "test-suite"           && break
-        [ "$comp" == bench     ] && _cabal_list                       "benchmark" && break
+    local Completion
+
+    for Completion in "$@"; do
+
+        [ "$Completion" == new-build   ] && _cabal_list_targets              && break
+        [ "$Completion" == new-repl    ] && _cabal_list_targets              && break
+        [ "$Completion" == new-run     ] && _cabal_list_targets "executable" && break
+        [ "$Completion" == new-test    ] && _cabal_list_targets "test-suite" && break
+        [ "$Completion" == new-bench   ] && _cabal_list_targets "benchmark"  && break
+        [ "$Completion" == new-haddock ] && _cabal_list_targets              && break
+
+        [ "$Completion" == new-install ] && _cabal_list_external_packages && break
+
+        [ "$Completion" == build     ] && _cabal_list_targets "executable|test-suite|benchmark" && break
+        [ "$Completion" == repl      ] && _cabal_list_targets "executable|test-suite|benchmark" && break
+        [ "$Completion" == run       ] && _cabal_list_targets "executable"                      && break
+        [ "$Completion" == test      ] && _cabal_list_targets            "test-suite"           && break
+        [ "$Completion" == bench     ] && _cabal_list_targets                       "benchmark" && break
+
     done
 }
 
+# NOTES
+#
+# [1] « $@ » will be the full command-line (so far).
+#
+# [2]
+#
+
+##################################################
+
 # List possible subcommands of a cabal subcommand.
 #
 # In example "sandbox" is a cabal subcommand that itself has subcommands. Since
 # "cabal --list-options" doesn't work in such cases we have to get the list
 # using other means.
-_cabal_subcommands()
+
+function _cabal_subcommands ()
+
 {
     local word
     for word in "$@"; do
@@ -54,7 +179,10 @@ _cabal_subcommands()
     done
 }
 
-__cabal_has_doubledash ()
+##################################################
+
+function __cabal_has_doubledash  ()
+
 {
     local c=1
     # Ignore the last word, because it is replaced anyways.
@@ -70,25 +198,34 @@ __cabal_has_doubledash ()
     return 1
 }
 
-_cabal()
+
+##################################################
+
+function _cabal ()
+
 {
     # no completion past cabal arguments.
     __cabal_has_doubledash && return
 
     # get the word currently being completed
-    local cur
-    cur=${COMP_WORDS[$COMP_CWORD]}
+    local CurrentWord
+    CurrentWord=${COMP_WORDS[$COMP_CWORD]}
 
     # create a command line to run
-    local cmd
+    local CommandLine
     # copy all words the user has entered
-    cmd=( ${COMP_WORDS[@]} )
+    CommandLine=( "${COMP_WORDS[@]}" )
 
     # replace the current word with --list-options
-    cmd[${COMP_CWORD}]="--list-options"
+    CommandLine[${COMP_CWORD}]="--list-options"
 
     # the resulting completions should be put into this array
-    COMPREPLY=( $( compgen -W "$( eval "${cmd[@]}" 2>/dev/null ) $( _cabal_targets "${cmd[@]}" ) $( _cabal_subcommands "${COMP_WORDS[@]}" )" -- "$cur" ) )
+    COMPREPLY=( $( compgen -W "$( eval "${CommandLine[@]}" 2>/dev/null ) $( _cabal_targets "${CommandLine[@]}" ) $( _cabal_subcommands "${COMP_WORDS[@]}" )" -- "$CurrentWord" ) )
 }
 
+# abc="a b c"
+# { IFS=" " read -a ExampleArray <<< "$abc"; echo ${ExampleArray[@]}; echo ${!ExampleArray[@]}; }
+
+##################################################
+
 complete -F _cabal -o default cabal