Add 'outdated' command.

src/main/bash/gvm-outdated.sh

@@ -0,0 +1,55 @@
+#!/bin/bash
+
+function __gvmtool_determine_outdated_version {
+    local candidate local_versions remote_default_version
+    candidate="$1"
+
+    # Resolve local versions
+    local_versions="$(echo $(find "${GVM_DIR}/${candidate}" -maxdepth 1 -mindepth 1 -type d -exec basename '{}' \;) | sed -e "s/ /, /g" )"
+    if [ ${#local_versions} -eq 0 ]; then
+        return 1
+    fi
+
+    # Resolve remote default version
+    remote_default_version="$(curl -s "${GVM_SERVICE}/candidates/${candidate}/default")"
+    if [ -z "$remote_default_version" ]; then
+        return 2
+    fi
+
+    # Check outdated or not
+    if [ ! -d "${GVM_DIR}/${candidate}/${remote_default_version}" ]; then
+        echo "${candidate} (${local_versions} < ${remote_default_version})"
+    fi
+}
+
+function __gvmtool_outdated {
+    local all candidates candidate outdated installed_count
+    if [ -n "$1" ]; then
+        all=false
+        candidates=$1
+    else
+        all=true
+        candidates=${GVM_CANDIDATES[@]}
+    fi
+    installed_count=0
+    for candidate in ${candidates}; do
+        outdated="$(__gvmtool_determine_outdated_version "${candidate}")"
+        case $? in
+            1)
+                $all || echo "Not using any version of ${candidate}"
+                ;;
+            2)
+                echo ""
+                echo "Stop! Could not get remote version of ${candidate}"
+                return 1
+                ;;
+            *)
+                [ -n "${outdated}" ] && echo "${outdated}"
+                (( installed_count += 1 ))
+                ;;
+        esac
+    done
+    if $all && [ ${installed_count} -eq 0 ]; then
+        echo 'No candidates are in use'
+    fi
+}

src/test/cucumber/gvm/outdated_candidate.feature

@@ -0,0 +1,43 @@
+Feature: Outdated Candidate
+
+  Background:
+    Given the internet is reachable
+    And an initialised environment
+
+  Scenario: Display outdated candidate version in use when it is outdated
+    Given the candidate "grails" version "1.3.9" is already installed and default
+    And the default "grails" candidate is "2.4.4"
+    When I enter "gvm outdated grails"
+    Then I see "grails (1.3.9 < 2.4.4)"
+
+  Scenario: Display outdated candidate version in use when it is not outdated
+    Given the candidate "grails" version "1.3.9" is already installed and default
+    And the default "grails" candidate is "1.3.9"
+    When I enter "gvm outdated grails"
+    Then I do not see "grails"
+
+  Scenario: Display outdated candidate version when none is in use
+    Given the candidate "grails" does not exist
+    When I enter "gvm outdated grails"
+    Then I see "Not using any version of grails"
+
+  Scenario: Display outdated candidate versions when none is specified and none is in use
+    Given the candidate "grails" does not exist
+    When I enter "gvm outdated"
+    Then I see "No candidates are in use"
+
+  Scenario: Display outdated candidate versions when none is specified and one is in use
+    Given the candidate "grails" version "1.3.9" is already installed and default
+    And the default "grails" candidate is "2.4.4"
+    When I enter "gvm outdated"
+    Then I see "grails (1.3.9 < 2.4.4)"
+
+  Scenario: Display outdated candidate versions when none is specified and multiple are in use
+    Given  the candidate "grails" version "1.3.9" is already installed and default
+    And the default "grails" candidate is "2.4.4"
+    And the candidate "groovy" version "2.0.5" is already installed and default
+    And the default "groovy" candidate is "2.4.1"
+    When I enter "gvm outdated"
+    Then I see "grails (1.3.9 < 2.4.4)"
+    And I see "groovy (2.0.5 < 2.4.1)"
+