IDEA-127533 int field is displayed as char - show only reasonable ascii as chars

src/org/jetbrains/java/decompiler/modules/decompiler/exps/ConstExprent.java

@@ -133,7 +133,7 @@ public class ConstExprent extends Exprent {
         String ret = CHAR_ESCAPES.get(val);
         if (ret == null) {
           char c = (char)val.intValue();
-          if (c >= 32 && c < 127 || !ascii && TextUtil.isPrintableUnicode(c)) {
+          if (isPrintableAscii(c) || !ascii && TextUtil.isPrintableUnicode(c)) {
             ret = String.valueOf(c);
           }
           else {
@@ -278,7 +278,7 @@ public class ConstExprent extends Exprent {
         //  buffer.append("\\\'");
         //  break;
         default:
-          if (c >= 32 && c < 127 || !ascii && TextUtil.isPrintableUnicode(c)) {
+          if (isPrintableAscii(c) || !ascii && TextUtil.isPrintableUnicode(c)) {
             buffer.append(c);
           }
           else {
@@ -371,7 +371,7 @@ public class ConstExprent extends Exprent {
     // BYTECHAR and SHORTCHAR => CHAR in the CHAR context
     if (expectedType.equals(VarType.VARTYPE_CHAR) &&
             (constType.equals(VarType.VARTYPE_BYTECHAR) || constType.equals(VarType.VARTYPE_SHORTCHAR))) {
-      if (getIntValue() != 0) {
+      if (isPrintableAscii(getIntValue())) {
         setConstType(VarType.VARTYPE_CHAR);
       }
     }
@@ -382,6 +382,11 @@ public class ConstExprent extends Exprent {
     }
   }
 
+  private static boolean isPrintableAscii(int c) {
+    return c >= 32 && c < 127;
+  }
+
+
   public Object getValue() {
     return value;
   }

testData/results/TestPrimitives.dec

@@ -69,6 +69,17 @@ public class TestPrimitives {
    public void constructor() {
       new Byte((byte)1);// 73
    }// 74
+
+   private boolean compare(char c) {
+      boolean res = c > -1;// 77
+      res = c > 0;// 78
+      res = c > 1;// 79
+      res = c > 'a';// 80
+      res = c > 'Z';// 81
+      res = c > 127;// 82
+      res = c > 255;// 83
+      return res;// 84
+   }
 }
 
 class 'pkg/TestPrimitives' {
@@ -210,6 +221,30 @@ class 'pkg/TestPrimitives' {
       4      69
       9      70
    }
+
+   method 'compare (C)Z' {
+      1      73
+      2      73
+      a      73
+      c      74
+      14      74
+      16      75
+      17      75
+      1f      75
+      21      76
+      23      76
+      2b      76
+      2d      77
+      2f      77
+      37      77
+      39      78
+      3b      78
+      43      78
+      45      79
+      48      79
+      50      79
+      52      80
+   }
 }
 
 Lines mapping:
@@ -248,3 +283,11 @@ Lines mapping:
 70 <-> 67
 73 <-> 70
 74 <-> 71
+77 <-> 74
+78 <-> 75
+79 <-> 76
+80 <-> 77
+81 <-> 78
+82 <-> 79
+83 <-> 80
+84 <-> 81

testData/src/pkg/TestPrimitives.java

@@ -72,4 +72,15 @@ public class TestPrimitives {
   public void constructor() {
     new Byte((byte)1);
   }
+
+  private boolean compare(char c) {
+    boolean res = (c > -1);
+    res = (c > 0);
+    res = (c > 1);
+    res = (c > 'a');
+    res = (c > 'Z');
+    res = (c > 127);
+    res = (c > 255);
+    return res;
+  }
 }