_ip_addresses: Add option to complete all/v4/v6 addresses, add unit test

bash_completion

@@ -912,15 +912,23 @@ _configured_interfaces()
 }
 
 # Local IP addresses.
+# -4: IPv4 addresses only (default)
+# -6: IPv6 addresses only
+# -a: All addresses
 #
 _ip_addresses()
 {
+    local n
+    case $1 in
+        -a) n='6\?' ;;
+        -6) n='6' ;;
+    esac
     local PATH=$PATH:/sbin
-    COMPREPLY+=( $( compgen -W \
-        "$( { LC_ALL=C ifconfig -a || ip addr show; } 2>/dev/null | command sed -ne \
+    local addrs=$( { LC_ALL=C ifconfig -a || ip addr show; } 2>/dev/null |
+        command sed -ne \
             's/.*addr:\([^[:space:]]*\).*/\1/p' -ne \
-            's|.*inet[[:space:]]\{1,\}\([^[:space:]/]*\).*|\1|p' )" \
-        -- "$cur" ) )
+            "s|.*inet$n[[:space:]]\{1,\}\([^[:space:]/]*\).*|\1|p" )
+    COMPREPLY+=( $( compgen -W "$addrs" -- "$cur" ) )
 }
 
 # This function completes on available kernels

test/unit/_ip_addresses.exp

@@ -0,0 +1,53 @@
+proc setup {} {
+    assert_bash_exec {unset COMPREPLY cur}
+    save_env
+
+    assert_bash_exec { \
+        _ia() { local cur=$(_get_cword);unset COMPREPLY;_ip_addresses; }; \
+        complete -F _ia ia \
+    }
+    assert_bash_exec { \
+        _iaa() { local cur=$(_get_cword);unset COMPREPLY;_ip_addresses -a; }; \
+        complete -F _iaa iaa \
+    }
+    assert_bash_exec { \
+        _ia6() { local cur=$(_get_cword);unset COMPREPLY;_ip_addresses -6; }; \
+        complete -F _ia6 ia6 \
+    }
+}
+
+proc teardown {} {
+    assert_bash_exec {unset COMPREPLY cur}
+    assert_bash_exec {unset -f _ia _iaa _ia6}
+    assert_env_unmodified
+}
+
+setup
+
+
+# TODO: add/robustify conditions on expected failures or unsupported setups
+#       ...so that there's no need for junk like CI/DIST special-casing
+
+set test "_ip_addresses should run without errors"
+assert_bash_exec {_ip_addresses} $test
+sync_after_int
+
+set test "_ip_addresses -a should complete ip addresses"
+assert_complete_any "iaa "
+sync_after_int
+
+set test "_ip_addresses should complete ipv4 addresses"
+assert_complete_any "ia "
+sync_after_int
+
+set test "_ip_addresses -6 should complete ipv6 addresses"
+if {[info exists ::env(CI)] &&
+    [info exists ::env(DIST)] && $::env(DIST) == "fedoradev"} {
+    unsupported $test
+} else {
+    assert_complete_any "ia6 "
+}
+sync_after_int
+
+
+teardown