Fix Psalm warnings

Makefile

@@ -1,7 +1,7 @@
 .PHONY: ci test prerequisites
 
 # Use any most recent PHP version
-PHP=$(shell which php7.4 || which php)
+PHP=$(shell which php)
 PHPDBG=$(shell which phpdbg && echo -qrr || echo php)
 
 # Default parallelism
@@ -34,7 +34,6 @@ PHPSTAN_ARGS=analyse src tests --level=2 -c .phpstan.neon
 # Psalm
 PSALM=vendor/bin/psalm
 PSALM_ARGS=--show-info=false
-PSALM_PHP_VERSION="PHP 7.3"
 
 # Composer
 COMPOSER=$(PHP) $(shell which composer)
@@ -44,7 +43,6 @@ INFECTION=vendor/bin/infection
 MIN_MSI=96
 MIN_COVERED_MSI=99
 INFECTION_ARGS=--min-msi=$(MIN_MSI) --min-covered-msi=$(MIN_COVERED_MSI) --threads=$(JOBS) --coverage=build/logs --log-verbosity=default --show-mutations --no-interaction
-INFECTION_PHP_VERSION="PHP 7.3"
 
 all: test
 

psalm.xml

@@ -3,55 +3,16 @@
     totallyTyped="true"
     allowPhpStormGenerics="true"
     cacheDirectory="build/"
+    errorLevel="5"
+    resolveFromConfigFile="true"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns="https://getpsalm.org/schema/config"
-    xsi:schemaLocation="https://getpsalm.org/schema/config file:///home/lesha/workspace/Cdek-SDK/vendor/vimeo/psalm/config.xsd"
+    xsi:schemaLocation="https://getpsalm.org/schema/config vendor/vimeo/psalm/config.xsd"
 >
     <projectFiles>
         <directory name="src" />
-        <directory name="examples" />
-        <directory name="tests/Integration" />
         <ignoreFiles>
             <directory name="vendor" />
         </ignoreFiles>
     </projectFiles>
-
-    <issueHandlers>
-        <LessSpecificReturnType errorLevel="info" />
-
-        <!-- level 3 issues - slightly lazy code writing, but provably low false-negatives -->
-
-        <DeprecatedMethod errorLevel="info" />
-        <DeprecatedProperty errorLevel="info" />
-        <DeprecatedClass errorLevel="info" />
-        <DeprecatedConstant errorLevel="info" />
-        <DeprecatedInterface errorLevel="info" />
-        <DeprecatedTrait errorLevel="info" />
-
-        <MissingClosureReturnType errorLevel="info" />
-        <MissingReturnType errorLevel="info" />
-        <MissingPropertyType errorLevel="info" />
-        <InvalidDocblock errorLevel="info" />
-        <MisplacedRequiredParam errorLevel="info" />
-
-        <PropertyNotSetInConstructor errorLevel="info" />
-        <MissingConstructor errorLevel="info" />
-        <MissingClosureParamType errorLevel="info" />
-        <MissingParamType errorLevel="info" />
-
-        <RedundantCondition errorLevel="info" />
-
-        <DocblockTypeContradiction errorLevel="info" />
-        <RedundantConditionGivenDocblockType errorLevel="info" />
-
-        <UnresolvableInclude errorLevel="info" />
-
-        <RawObjectIteration errorLevel="info" />
-        <ImplementedReturnTypeMismatch errorLevel="info" />
-
-        <PossiblyInvalidMethodCall errorLevel="info" />
-        <PossiblyInvalidArgument errorLevel="info" />
-
-        <ReservedWord errorLevel="info" />
-    </issueHandlers>
 </psalm>