fix(export-values): propagate result of export-values to all parent charts Values

When we defined some Values in the subchart and also some of these
Values defined in this chart's parents and we are passing some values
via export-values to the same keys, then the merge result was wrong.

Signed-off-by: Ilya Lesikov <ilya@lesikov.com>

pkg/chartutil/dependencies.go

@@ -324,10 +324,61 @@ func processExportValues(c *chart.Chart) error {
 		return err
 	}
 
+	ev, err := copystructure.Copy(exportedValues)
+	if err != nil {
+		return err
+	}
+
 	// Merge newly generated extra Values map into current chart Values.
-	c.Values = CoalesceTables(exportedValues, cv.(Values))
+	c.Values = CoalesceTables(ev.(map[string]interface{}), cv.(Values))
+
+	evForSync, err := copystructure.Copy(exportedValues)
+	if err != nil {
+		return err
+	}
+
+	// Make sure no parent chart will override our new extra Values in this chart.
+	if err := syncChartOverridesToParentsValues(c, evForSync.(map[string]interface{})); err != nil {
+		return err
+	}
+
+	return nil
+}
 
+// Get Values map with overrides destined for current chart and merge these overrides into all its parent charts
+// Values, while prefixing the to be applied parent overrides with the relative path to the current chart. This is
+// to avoid values from parent charts having precedence to the overrides passed to the current chart.
+func syncChartOverridesToParentsValues(c *chart.Chart, overrides map[string]interface{}) error {
+	if c.Parent() == nil {
 		return nil
+	}
+
+	// Get parent chart values.
+	pvals, err := CoalesceValues(c.Parent(), nil)
+	if err != nil {
+		return err
+	}
+
+	pv, err := copystructure.Copy(pvals)
+	if err != nil {
+		return err
+	}
+
+	o, err := copystructure.Copy(overrides)
+	if err != nil {
+		return err
+	}
+
+	parentOverrides := pathToMap(c.Name(), o.(map[string]interface{}))
+
+	po, err := copystructure.Copy(parentOverrides)
+	if err != nil {
+		return err
+	}
+
+	c.Parent().Values = CoalesceTables(po.(map[string]interface{}), pv.(Values))
+
+	return syncChartOverridesToParentsValues(c.Parent(), parentOverrides)
 }
 
 // Extend extra Values overrides according to export-values directive, if needed.