Display how many reviews there are for a CPT - php

Question

I have two custom post types, 'product' and 'product_review'. The CPT 'product_review' has a taxonomy 'product_name' whose slug matches the CPT 'product'
An example 'Product A' is the product post. 'Product Review A' is the product_review post that has a 'product_name' taxonomy value of 'product_a'.
I need to show how many 'product_review' each 'product' has.
<?php
global $post;
$post_slug = $post->post_name;
//echo $post_slug;
//this outputs the name of the product, which I need
$terms = get_terms('product_review');
foreach ( $terms as $post_slug ) {
echo $term->count . 'Reviews';
?>
It doesn't show any count. I want it to show how many $terms(how many reviews) are tied to $post_slug(name of product). The 'product_review' slug matches the slug of the product.

Answer 1

You can use a custom WP_Query and the found_posts prop like below:
// example query args
$args = [
// look for reviews cpt
'post_type' => 'product_review',
// limit to posts that match our taxonomy product name
'tax_query' => [
[
'taxonomy' => 'product_name',
'field' => 'slug',
'terms' => [ 'product_a' ]
]
]
];
// run the query
$query = new WP_Query( $args );
// grab "total" found posts
$total = $query->found_posts;
// display the total
echo $total
// reset post data so we dont break the main loop
wp_reset_postdata();

Answer 2

#mikerojas answer got me close, but wasn't returning accurate data. Here is what I came up with that got me what I needed.
<?php
$review_args = array(
'post_type' => 'my_post_type',
'post_status' => 'publish',
'tax_query' => array(
array (
'taxonomy' => 'my_taxonomy',
'field' => 'slug',
//this is already inside a loop, making it dynamic to only grab the reviews whose tax value equals the post slut
'terms' => $post->post_name,
)
),
);
if($num = count( get_posts ( $review_args)) <= 1) {
echo 'Review ' . $num = count( get_posts( $review_args ) );
} else {
echo 'Reviews ' . $num = count( get_posts( $review_args ) );
}
wp_reset_postdata();
?>