From 693c5d873aea249a4bbe43225254a4479a4a5aa6 Mon Sep 17 00:00:00 2001
From: Gabriel Gilder <gabriel@gabrielgilder.com>
Date: Mon, 22 May 2023 14:35:57 -0700
Subject: [PATCH] Fix total coverage calculation

Per https://confluence.atlassian.com/pages/viewpage.action?pageId=79986990 which is already referenced for the calculation:

    So in order to calculate the Total Percentage Coverage metric using data from an XML report you have to use the following equation:

    TPC = (coveredconditionals + coveredstatements + coveredmethods) / (conditionals + statements + methods)

Using elements is incorrect because, as that page notes, "elements" is
conditionals + statements, which means the previous calculation would
double-count statements.

Also, the clover-format XML includes multiple `metrics` elements which
were being redundantly counted. Each `file` element contains a
`metrics` element, but then there is also a `metrics` element within
each `class` defined in that file. Finally, there is a `project` level
`metrics` element which summarizes all the files tested.

Therefore, we only need to pick out the `project` level element to get
the total metrics, and the summing is not necessary. However, I've left
the summing in place so that this could be extended with, for instance,
a coverage check on only modified files.
---
 coverage-check.php | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/coverage-check.php b/coverage-check.php
index 5720ad3..e088e10 100755
--- a/coverage-check.php
+++ b/coverage-check.php
@@ -4,7 +4,7 @@
 
 // Inspired by: https://ocramius.github.io/blog/automated-code-coverage-check-for-github-pull-requests-with-travis/
 
-const XPATH_METRICS = '//metrics';
+const XPATH_METRICS = '//project/metrics';
 const STATUS_OK = 0;
 const STATUS_ERROR = 1;
 
@@ -42,16 +42,16 @@ function printStatus(string $msg, int $exitCode = STATUS_OK)
 $inputFile = $argv[1];
 $percentage = min(100, max(0, (float) $argv[2]));
 
-$elements = 0;
-$coveredElements = 0;
+$conditionals = 0;
+$coveredconditionals = 0;
 $statements = 0;
 $coveredstatements = 0;
 $methods = 0;
 $coveredmethods = 0;
 
 foreach (loadMetrics($inputFile) as $metric) {
-    $elements += (int) $metric['elements'];
-    $coveredElements += (int) $metric['coveredelements'];
+    $conditionals += (int) $metric['conditionals'];
+    $coveredconditionals += (int) $metric['coveredconditionals'];
     $statements += (int) $metric['statements'];
     $coveredstatements += (int) $metric['coveredstatements'];
     $methods += (int) $metric['methods'];
@@ -59,8 +59,8 @@ function printStatus(string $msg, int $exitCode = STATUS_OK)
 }
 
 // See calculation: https://confluence.atlassian.com/pages/viewpage.action?pageId=79986990
-$coveredMetrics = $coveredstatements + $coveredmethods + $coveredElements;
-$totalMetrics = $statements + $methods + $elements;
+$coveredMetrics = $coveredstatements + $coveredmethods + $coveredconditionals;
+$totalMetrics = $statements + $methods + $conditionals;
 
 if ($totalMetrics === 0) {
     printStatus('Insufficient data for calculation. Please add more code.', STATUS_ERROR);