Check for missed columns even if given and expected column count are the same

csv/src/main/java/tools/jackson/dataformat/csv/CsvParser.java

@@ -655,15 +655,17 @@ protected void _readHeaderLine() throws JacksonException {
                 _reportCsvReadError("Empty header line: can not bind data");
             }
         }
-        // [dataformats-text#285]: Are we missing something?
-        int diff = schemaColumnCount - newColumnCount;
-        if ((diff > 0) && CsvReadFeature.FAIL_ON_MISSING_HEADER_COLUMNS.enabledIn(_formatFeatures)) {
+
+        if (CsvReadFeature.FAIL_ON_MISSING_HEADER_COLUMNS.enabledIn(_formatFeatures)) {
             Set<String> oldColumnNames = new LinkedHashSet<>();
             _schema.getColumnNames(oldColumnNames);
             oldColumnNames.removeAll(newSchema.getColumnNames());
-            _reportCsvReadError(String.format("Missing %d header column%s: [\"%s\"]",
-                    diff, (diff == 1) ? "" : "s",
-                            String.join("\",\"", oldColumnNames)));
+            var diff = oldColumnNames.size();
+            if (diff > 0) {
+                _reportCsvReadError(String.format("Missing %d header column%s: [\"%s\"]",
+                    diff, (diff == 1) ? "" : "s", String.join("\",\"", oldColumnNames)
+                ));
+            }
         }
 
         // otherwise we will use what we got

csv/src/test/java/tools/jackson/dataformat/csv/deser/MissingColumns579Test.java

@@ -0,0 +1,50 @@
+package tools.jackson.dataformat.csv.deser;
+
+import org.junit.jupiter.api.Test;
+import tools.jackson.databind.MappingIterator;
+import tools.jackson.dataformat.csv.CsvMapper;
+import tools.jackson.dataformat.csv.CsvReadException;
+import tools.jackson.dataformat.csv.CsvSchema;
+import tools.jackson.dataformat.csv.ModuleTestBase;
+
+import java.util.Map;
+
+import static org.junit.jupiter.api.Assertions.fail;
+
+/**
+ * Tests for cases where csv doesn't contain columns from predefined schema
+ */
+public class MissingColumns579Test extends ModuleTestBase
+{
+    /*
+    /**********************************************************************
+    /* Test methods
+    /**********************************************************************
+     */
+
+    private final CsvMapper MAPPER = mapperForCsv();
+    private final CsvSchema csvSchema = CsvSchema.builder()
+            .setUseHeader(true)
+            .setReorderColumns(true)
+            .addColumn("name")
+            .addColumn("age")
+            .build();
+    private final String CSV = "name,agee\nRoger,18\n";
+
+    // [dataformats-text#579]: fail when predefined schema have the same number
+    // of columns as the populated, but column names are differs
+    @Test
+    public void testFailOnMissingWithReorder() throws Exception
+    {
+        try {
+            MappingIterator<Map<String, Object>> it = MAPPER
+                .readerFor(Map.class)
+                .with(csvSchema)
+                .readValues(CSV);
+            it.nextValue();
+            fail("Should not pass with missing columns");
+        } catch (CsvReadException e) {
+            verifyException(e, "Missing 1 header column: [\"age\"]");
+        }
+    }
+}