MDL-55108 core: Document the charting library

Part of MDL-54987 epic.

lib/classes/chart_axis.php

@@ -38,46 +38,97 @@ use renderable;
  */
 class chart_axis implements JsonSerializable {
 
+    /** Default axis position. */
     const POS_DEFAULT = null;
+    /** Bottom axis position. */
     const POS_BOTTOM = 'bottom';
+    /** Left axis position. */
     const POS_LEFT = 'left';
+    /** Right axis position. */
     const POS_RIGHT = 'right';
+    /** Top axis position. */
     const POS_TOP = 'top';
 
+    /** @var string The axis label. */
     protected $label = null;
+    /** @var string[] The axis labels, tick values. */
     protected $labels = null;
+    /** @var float The maximum tick value. */
     protected $max = null;
+    /** @var float The minimum tick value. */
     protected $min = null;
+    /** @var string The axis position. */
     protected $position = self::POS_DEFAULT;
+    /** @var float The stepsize between ticks. */
     protected $stepsize = null;
 
+    /**
+     * Constructor.
+     *
+     * Must not take any argument.
+     */
     public function __construct() {
     }
 
+    /**
+     * Get the label.
+     *
+     * @return string
+     */
     public function get_label() {
         return $this->label;
     }
 
+    /**
+     * Get the labels.
+     *
+     * @return string[]
+     */
     public function get_labels() {
         return $this->labels;
     }
 
+    /**
+     * Get the max value.
+     *
+     * @return float
+     */
     public function get_max() {
         return $this->max;
     }
 
+    /**
+     * Get the min value.
+     *
+     * @return float
+     */
     public function get_min() {
         return $this->min;
     }
 
+    /**
+     * Get the axis position.
+     *
+     * @return string
+     */
     public function get_position() {
         return $this->position;
     }
 
+    /**
+     * Get the step size.
+     *
+     * @return float
+     */
     public function get_stepsize() {
         return $this->stepsize;
     }
 
+    /**
+     * Serialize the object.
+     *
+     * @return array
+     */
     public function jsonSerialize() {
         return [
             'label' => $this->label,
@@ -89,28 +140,58 @@ class chart_axis implements JsonSerializable {
         ];
     }
 
+    /**
+     * Set the label.
+     *
+     * @param string $label The label.
+     */
     public function set_label($label) {
-        return $this->label = $label;
+        $this->label = $label;
     }
 
+    /**
+     * Set the labels.
+     *
+     * @param string[] $labels The labels.
+     */
     public function set_labels($labels) {
-        return $this->labels = $labels;
+        $this->labels = $labels;
     }
 
+    /**
+     * Set the max value.
+     *
+     * @param float $max The max value.
+     */
     public function set_max($max) {
-        return $this->max = $max;
+        $this->max = $max;
     }
 
+    /**
+     * Set the min value.
+     *
+     * @param float $min The min value.
+     */
     public function set_min($min) {
-        return $this->min = $min;
+        $this->min = $min;
     }
 
+    /**
+     * Set the position.
+     *
+     * @param string $position Use constant self::POS_*.
+     */
     public function set_position($position) {
-        return $this->position = $position;
+        $this->position = $position;
     }
 
+    /**
+     * Set the step size.
+     *
+     * @param float $stepsize The step size.
+     */
     public function set_stepsize($stepsize) {
-        return $this->stepsize = $stepsize;
+        $this->stepsize = $stepsize;
     }
 
 }