1 files changed, 27 insertions, 0 deletions
diff --git a/jstests/explain8.js b/jstests/explain8.js
new file mode 100644
index 00000000000..2e8c24cab50
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+++ b/jstests/explain8.js
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+// Test calculation of the 'millis' field in explain output.
+
+t = db.jstests_explain8;
+t.drop();
+
+t.ensureIndex( { a:1 } );
+for( i = 1000; i < 4000; i += 1000 ) {
+    t.save( { a:i } );
+}
+
+// Run a query with one $or clause per a-value, each of which sleeps for 'a' milliseconds.
+function slow() {
+    sleep( this.a );
+    return true;
+}
+clauses = [];
+for( i = 1000; i < 4000; i += 1000 ) {
+    clauses.push( { a:i, $where:slow } );
+}
+explain = t.find( { $or:clauses } ).explain( true );
+//printjson( explain );
+
+// Verify the duration of the whole query, and of each clause.
+assert.gt( explain.millis, 1000 - 500 + 2000 - 500 + 3000 - 500 );
+for( j = 0; j < 3; ++j ) {
+    assert.gt( explain.clauses[ j ].millis, ( j + 1 ) * 1000 - 500 );
+}