Extend getLastError to all calls

Fixes GitHub issue phpredis#245.

Author: nicolasff

README.markdown

@@ -2472,7 +2472,7 @@ $redis->script('exists', $script1, [$script2, $script3, ...]);
 
 ## getLastError
 ##### Description
-The last error message (if any) returned from a SCRIPT call
+The last error message (if any)
 ##### Parameters
 *none*  
 ##### Return Value

library.c

@@ -172,6 +172,7 @@ PHPAPI char *redis_sock_read(RedisSock *redis_sock, int *buf_len TSRMLS_DC)
 {
     char inbuf[1024];
     char *resp = NULL;
+    size_t err_len;
 
     if(-1 == redis_check_eof(redis_sock TSRMLS_CC)) {
         return NULL;
@@ -189,6 +190,8 @@ PHPAPI char *redis_sock_read(RedisSock *redis_sock, int *buf_len TSRMLS_DC)
 
     switch(inbuf[0]) {
         case '-':
+			err_len = strlen(inbuf+1) - 2;
+			redis_sock_set_err(redis_sock, inbuf+1, err_len);
 			/* stale data */
 			if(memcmp(inbuf + 1, "-ERR SYNC ", 10) == 0) {
 				zend_throw_exception(redis_exception_ce, "SYNC with master in progress", 0 TSRMLS_CC);

tests/TestRedis.php

@@ -3023,8 +3023,16 @@ public function testGetLastError() {
     	$this->redis->eval("not-a-lua-script");
 
     	// Now we should have an error
-    	$this->assertTrue(strlen($this->redis->getLastError()) > 0);
-    }
+		$evalError = $this->redis->getLastError();
+		$this->assertTrue(strlen($evalError) > 0);
+
+		// test getLastError with a regular command
+		$this->redis->set('x', 'a');
+		$this->assertFalse($this->redis->incr('x'));
+		$incrError = $this->redis->getLastError();
+		$this->assertTrue($incrError !== $evalError); // error has changed
+		$this->assertTrue(strlen($incrError) > 0);
+	}
 
     // Helper function to compare nested results -- from the php.net array_diff page, I believe
     private function array_diff_recursive($aArray1, $aArray2) {