Fix complex __repr__ formatting

Author: steve-s

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/complex/ComplexBuiltins.java

@@ -723,11 +723,11 @@ PNotImplemented doGeneric(Object left, Object right) {
     @Builtin(name = __REPR__, minNumOfPositionalArgs = 1)
     abstract static class ReprNode extends PythonUnaryBuiltinNode {
         @Specialization
-        @TruffleBoundary
         String repr(PComplex self) {
             return repr(self, getCore());
         }
 
+        @TruffleBoundary
         private static String repr(PComplex self, PythonCore core) {
             ComplexFormatter formatter = new ComplexFormatter(core, new Spec(-1, Spec.NONE));
             formatter.format(self);

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/formatting/ComplexFormatter.java

@@ -54,19 +54,17 @@ protected ComplexFormatter(PythonCore core, FormattingBuffer result, Spec spec)
         Spec imSpec;
         if (hasNoSpecType()) {
             // no type spec: should be like the default __str__
-            reSpec = getComponentSpecForNoSpecType(InternalFormat.Spec.NONE);
-            imSpec = getComponentSpecForNoSpecType('+');
+            reSpec = getComponentSpecForNoSpecType(spec, InternalFormat.Spec.NONE);
+            imSpec = getComponentSpecForNoSpecType(spec, '+');
         } else {
             // Turn off any flags that should apply to the result as a whole and not to the
-            // individual
-            // components (re/im). Sign of re is determined by the sign flag, sign of im will be
-            // always
-            // printed ('+' flag)
+            // individual components (re/im). Sign of re is determined by the sign flag, sign of im
+            // will be always printed ('+' flag)
             reSpec = getComponentSpec(spec, spec.sign);
             imSpec = getComponentSpec(spec, '+');
         }
-        reFormatter = new FloatFormatter(core, result, reSpec);
-        imFormatter = new FloatFormatter(core, result, imSpec);
+        reFormatter = new FloatFormatter(core, result, reSpec, false);
+        imFormatter = new FloatFormatter(core, result, imSpec, false);
     }
 
     public ComplexFormatter(PythonCore core, Spec spec) {
@@ -85,10 +83,17 @@ private static Spec getComponentSpec(Spec spec, char sign) {
                         spec.type);
     }
 
-    private static Spec getComponentSpecForNoSpecType(char sign) {
+    private static Spec getComponentSpecForNoSpecType(Spec spec, char sign) {
         // CPython uses "r" type, but also some internal flags that cause that integer values
         // are printed without the decimal part, which is mostly what "g" does
-        return new InternalFormat.Spec(' ', '>', sign, false, InternalFormat.Spec.UNSPECIFIED, Spec.NONE, -1, 'g');
+        int precision = spec.precision;
+        char type = 'r';
+        if (precision < 0) {
+            precision = 0;
+        } else {
+            type = 'g';
+        }
+        return new InternalFormat.Spec(' ', '>', sign, false, InternalFormat.Spec.UNSPECIFIED, Spec.NONE, precision, type);
     }
 
     private boolean hasNoSpecType() {

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/formatting/FloatFormatter.java

@@ -46,10 +46,14 @@ public class FloatFormatter extends InternalFormat.Formatter {
      *
      * @param result destination buffer
      * @param spec parsed conversion specification
+     * @param addDot0 reflects flag {@code Py_DTSF_ADD_DOT_0} in CPython, applicable only for 'r'
+     *            specifier
      */
-    public FloatFormatter(PythonCore core, FormattingBuffer result, Spec spec) {
+    public FloatFormatter(PythonCore core, FormattingBuffer result, Spec spec, boolean addDot0) {
         super(core, result, spec);
-        if (spec.alternate) {
+        if (!addDot0 && spec.type == 'r') {
+            minFracDigits = 0;
+        } else if (spec.alternate) {
             // Alternate form means do not trim the zero fractional digits.
             minFracDigits = -1;
         } else if (spec.type == 'r' || spec.type == Spec.NONE) {
@@ -64,11 +68,10 @@ public FloatFormatter(PythonCore core, FormattingBuffer result, Spec spec) {
         }
     }
 
-    /**
-     * Construct the formatter from a specification, allocating a buffer internally for the result.
-     *
-     * @param spec parsed conversion specification
-     */
+    public FloatFormatter(PythonCore core, FormattingBuffer result, Spec spec) {
+        this(core, result, spec, true);
+    }
+
     public FloatFormatter(PythonCore core, Spec spec) {
         this(core, new FormattingBuffer.StringFormattingBuffer(size(spec)), spec);
     }