use lint checker

.drone.yml

@@ -1,6 +1,12 @@
 pipeline:
+  lint:
+    image: nextcloudci/android:android-18
+    commands:
+      - export BRANCH=$(scripts/lint/getBranchName.sh ${GIT_USERNAME} ${GIT_TOKEN} ${DRONE_PULL_REQUEST})
+      - ruby scripts/lint/lint-up.rb ${GIT_USERNAME} ${GIT_TOKEN} $BRANCH
+
   test:
-    image: nextcloudci/android:android-17
+    image: nextcloudci/android:android-18
     commands:
       # uncomment gplay for Gplay, Modified only
       - sh -c "if [ '$FLAVOUR' != 'Generic' ]; then sed -i '/com.google.*.gms/s/^.*\/\///g' build.gradle; fi"

scripts/lint/getBranchName.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+# $1: username, $2: password/token, $3: pull request number
+
+curl 2>/dev/null -u $1:$2 https://api.github.com/repos/nextcloud/android/pulls/$3 | grep \"ref\": | grep -v master | cut -d"\"" -f4

scripts/lint/lint-results.txt

@@ -0,0 +1,2 @@
+DO NOT TOUCH; GENERATED BY TRAVIS
+      <span class="mdl-layout-title">Lint Report: 1000 errors and 863 warnings</span>

scripts/lint/lint-up.rb

@@ -0,0 +1,188 @@
+## Script from https://github.com/tir38/android-lint-entropy-reducer at 07.05.2017
+# adapts to drone, use git username / token as parameter
+
+puts "=================== starting Android Lint Entropy Reducer ===================="
+git_user, git_token, git_branch = ARGV
+
+# ========================  SETUP ============================
+
+# User name for git commits made by this script.
+TRAVIS_GIT_USERNAME = String.new("Travis CI server")
+
+# File name and relative path of generated Lint report. Must match build.gradle file:
+#   lintOptions {
+#       htmlOutput file("[FILE_NAME].html")
+#   }
+LINT_REPORT_FILE = String.new("build/reports/lint/lint.html")
+
+# File name and relative path of previous results of this script.
+PREVIOUS_LINT_RESULTS_FILE=String.new("scripts/lint/lint-results.txt")
+
+# Flag to evaluate warnings. true = check warnings; false = ignore warnings
+CHECK_WARNINGS = true
+
+# File name and relative path to custom lint rules; Can be null or "".
+CUSTOM_LINT_FILE = String.new("")
+
+# ================ SETUP DONE; DON'T TOUCH ANYTHING BELOW  ================
+
+require 'fileutils'
+require 'pathname'
+require 'open3'
+
+# since we need the xml-simple gem, and we want this script self-contained, let's grab it just when we need it
+begin
+    gem "xml-simple"
+    rescue LoadError
+    system("gem install xml-simple")
+    Gem.clear_paths
+end
+
+require 'xmlsimple'
+
+# add custom Lint jar
+if CUSTOM_LINT_FILE != nil &&
+    CUSTOM_LINT_FILE.length > 0
+
+    ENV["ANDROID_LINT_JARS"] = Dir.pwd + "/" + CUSTOM_LINT_FILE
+    puts "adding custom lint rules to default set: "
+    puts ENV["ANDROID_LINT_JARS"]
+end
+
+# run Lint
+puts "running Lint..."
+system './gradlew clean lint'
+
+# confirm that Lint ran w/out error
+result = $?.to_i
+if result != 0
+    puts "FAIL: failed to run ./gradlew clean lint"
+    exit 1
+end
+
+# find Lint report file
+lint_reports = Dir.glob(LINT_REPORT_FILE)
+if lint_reports.length == 0
+    puts "Lint HTML report not found."
+    exit 1
+end
+lint_report = String.new(lint_reports[0])
+
+# find error/warning count string in HTML report
+error_warning_string = ""
+File.open lint_report do |file|
+  error_warning_string = file.find { |line| line =~ /[0-9]* errors and [0-9]* warnings/ }
+end
+
+# find number of errors
+error_string = error_warning_string.match(/[0-9]* errors/)[0]
+current_error_count = error_string.match(/[0-9]*/)[0].to_i
+puts "found errors: " + current_error_count.to_s
+
+# find number of warnings
+if CHECK_WARNINGS == true
+    warning_string = error_warning_string.match(/[0-9]* warnings/)[0]
+    current_warning_count = warning_string.match(/[0-9]*/)[0].to_i
+    puts "found warnings: " + current_warning_count.to_s
+end
+
+# get previous error and warning counts from last successful build
+
+previous_results = false
+
+previous_lint_reports = Dir.glob(PREVIOUS_LINT_RESULTS_FILE)
+if previous_lint_reports == nil ||
+    previous_lint_reports.length == 0
+
+    previous_lint_report = File.new(PREVIOUS_LINT_RESULTS_FILE, "w") # create for writing to later
+else
+    previous_lint_report = String.new(previous_lint_reports[0])
+
+    previous_error_warning_string = ""
+    File.open previous_lint_report do |file|
+      previous_error_warning_string = file.find { |line| line =~ /[0-9]* errors and [0-9]* warnings/ }
+    end
+
+    unless previous_error_warning_string.nil?
+        previous_results = true
+
+        previous_error_string = previous_error_warning_string.match(/[0-9]* errors/)[0]
+        previous_error_count = previous_error_string.match(/[0-9]*/)[0].to_i
+        puts "previous errors: " + previous_error_count.to_s
+
+        if CHECK_WARNINGS == true
+            previous_warning_string = previous_error_warning_string.match(/[0-9]* warnings/)[0]
+            previous_warning_count = previous_warning_string.match(/[0-9]*/)[0].to_i
+            puts "previous warnings: " + previous_warning_count.to_s
+        end
+    end
+end
+
+# compare previous error count with current error count
+if previous_results == true  &&
+    current_error_count > previous_error_count
+    puts "FAIL: error count increased"
+    exit 1
+end
+
+# compare previous warning count with current warning count
+if CHECK_WARNINGS  == true &&
+    previous_results == true &&
+    current_warning_count > previous_warning_count
+
+    puts "FAIL: warning count increased"
+    exit 1
+end
+
+# check if warning and error count stayed the same
+if  previous_results == true &&
+    current_error_count == previous_error_count &&
+    current_warning_count == previous_warning_count
+
+    puts "SUCCESS: count stayed the same"
+    exit 0
+end
+
+# either error count or warning count DECREASED
+
+# write new results to file (will overwrite existing, or create new)
+File.write(previous_lint_report, "DO NOT TOUCH; GENERATED BY TRAVIS\n" + error_warning_string)
+
+# get user, token from arguments
+git_user, git_token = ARGV
+
+# push changes to github (if this script is run locally, we don't want to overwrite git username and email, so save temporarily)
+previous_git_username, st = Open3.capture2('git config user.name')
+previous_git_username = previous_git_username.strip
+
+previous_git_email, st = Open3.capture3('git config user.email')
+previous_git_email = previous_git_email.strip
+
+# update git user name and email for this script
+system ("git config --local user.name '"  + git_user + "'")
+system ("git config --local user.email '.'") # set email blank
+system ("git remote rm origin")
+system ("git remote add origin https://" + git_user + ":" + git_token + "@github.com/nextcloud/android")
+
+# add previous Lint result file to git
+system ('git add ' + PREVIOUS_LINT_RESULTS_FILE)
+
+# Travis has git in a detached head here. Let's get on the right branch.
+travis_branch_name = ENV['TRAVIS_BRANCH']
+if travis_branch_name != nil
+    system ('git checkout ' + travis_branch_name)
+end
+
+# commit changes; Add "skip ci" so that we don't accidentally trigger another Travis build
+system ('git commit -m "Travis: update Lint results to reflect reduced error/warning count [skip ci]" ')
+
+# push to origin
+system("git config push.default simple")
+system ("git push")
+
+# restore previous git user name and email
+system("git config --local user.name '#{previous_git_username}'")
+system("git config --local user.email '#{previous_git_email}'")
+
+puts "SUCCESS: count was reduced"
+exit 0 # success