add psalm to phive and Makefile, init psalm - level 3

.phive/phars.xml

@@ -3,5 +3,6 @@
   <phar name="php-cs-fixer" version="^2.16.3" installed="2.16.3" location="./tools/php-cs-fixer" copy="true"/>
   <phar name="phpunit" version="^8.5.6" installed="8.5.6" location="./tools/phpunit" copy="true"/>
   <phar name="phpstan" version="^0.12.29" installed="0.12.29" location="./tools/phpstan" copy="true"/>
+  <phar name="psalm" version="^3.12.2" installed="3.12.2" location="./tools/psalm" copy="true"/>
   <phar name="humbug/box" version="^3.8.4" installed="3.8.4" location="./tools/box" copy="true"/>
 </phive>

Makefile

@@ -4,6 +4,7 @@ PHP_BIN := php
 PHIVE_BIN := phive
 PHP_CS_FIXER_BIN := ./tools/php-cs-fixer
 PHPSTAN_BIN	:= ./tools/phpstan
+PSALM_BIN	:= ./tools/psalm
 PHPUNIT_BIN	:= ./tools/phpunit
 
 .PHONY: build tools-install composer-install tests tests-coverage gpg php-cs-check php-cs-fix phpstan
@@ -34,6 +35,9 @@ php-cs-fix:																		## run cs fixer
 phpstan:
 	$(PHPSTAN_BIN) analyse
 
+psalm:
+	$(PSALM_BIN) analyse
+
 gpg:
 	gpg --detach-sign --armor --output deptrac.phar.asc deptrac.phar
 	gpg --verify deptrac.phar.asc deptrac.phar

psalm.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0"?>
+<psalm
+    errorLevel="3"
+    resolveFromConfigFile="true"
+    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns="https://getpsalm.org/schema/config"
+    xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
+>
+    <projectFiles>
+        <directory name="src" />
+        <ignoreFiles>
+            <directory name="vendor" />
+        </ignoreFiles>
+    </projectFiles>
+</psalm>