starlark: move MethodLibrary.parseInt to StarlarkInt
Also:
- simplify prefix logic, avoiding hash table.
- fix bug that allowed two signs ("-0x-10"), and test.
PiperOrigin-RevId: 339374232
diff --git a/src/main/java/net/starlark/java/eval/MethodLibrary.java b/src/main/java/net/starlark/java/eval/MethodLibrary.java
index cd24351..ebb91e0 100644
--- a/src/main/java/net/starlark/java/eval/MethodLibrary.java
+++ b/src/main/java/net/starlark/java/eval/MethodLibrary.java
@@ -15,17 +15,14 @@
package net.starlark.java.eval;
import com.google.common.base.Ascii;
-import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;
import com.google.common.collect.Ordering;
-import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
-import javax.annotation.Nullable;
import net.starlark.java.annot.Param;
import net.starlark.java.annot.ParamType;
import net.starlark.java.annot.StarlarkBuiltin;
@@ -396,9 +393,6 @@
}
}
- private static final ImmutableMap<String, Integer> INT_PREFIXES =
- ImmutableMap.of("0b", 2, "0o", 8, "0x", 16);
-
@StarlarkMethod(
name = "int",
doc =
@@ -480,80 +474,6 @@
throw Starlark.errorf("got %s, want string, int, float, or bool", Starlark.type(x));
}
- // TODO(adonovan): move into StarlarkInt.parse in a follow-up.
- static StarlarkInt parseInt(String string, int base) throws NumberFormatException {
- String stringForErrors = string;
-
- boolean isNegative = false;
- if (string.isEmpty()) {
- throw new NumberFormatException("empty string");
- }
- char c = string.charAt(0);
- if (c == '+') {
- string = string.substring(1);
- } else if (c == '-') {
- string = string.substring(1);
- isNegative = true;
- }
-
- String prefix = getIntegerPrefix(string);
- String digits;
- if (prefix == null) {
- // Nothing to strip. Infer base 10 if autodetection was requested (base == 0).
- digits = string;
- if (base == 0) {
- if (string.length() > 1 && string.startsWith("0")) {
- // We don't infer the base when input starts with '0' (due
- // to confusion between octal and decimal).
- throw new NumberFormatException(
- "cannot infer base when string begins with a 0: " + Starlark.repr(stringForErrors));
- }
- base = 10;
- }
- } else {
- // Strip prefix. Infer base from prefix if unknown (base == 0), or else verify its
- // consistency.
- digits = string.substring(prefix.length());
- int expectedBase = INT_PREFIXES.get(prefix);
- if (base == 0) {
- base = expectedBase;
- } else if (base != expectedBase) {
- throw new NumberFormatException(
- String.format(
- "invalid base-%d literal: %s (%s prefix wants base %d)",
- base, Starlark.repr(stringForErrors), prefix, expectedBase));
- }
- }
-
- if (base < 2 || base > 36) {
- throw new NumberFormatException(
- String.format("invalid base %d (want 2 <= base <= 36)", base));
- }
- StarlarkInt result;
- try {
- result = StarlarkInt.of(Long.parseLong(digits, base));
- } catch (NumberFormatException unused1) {
- try {
- result = StarlarkInt.of(new BigInteger(digits, base));
- } catch (NumberFormatException unused2) {
- throw new NumberFormatException(
- String.format("invalid base-%d literal: %s", base, Starlark.repr(stringForErrors)));
- }
- }
- return isNegative ? StarlarkInt.uminus(result) : result;
- }
-
- @Nullable
- private static String getIntegerPrefix(String value) {
- value = Ascii.toLowerCase(value);
- for (String prefix : INT_PREFIXES.keySet()) {
- if (value.startsWith(prefix)) {
- return prefix;
- }
- }
- return null;
- }
-
@StarlarkMethod(
name = "dict",
doc =
diff --git a/src/main/java/net/starlark/java/eval/StarlarkInt.java b/src/main/java/net/starlark/java/eval/StarlarkInt.java
index 1cc6041..f70f38e 100644
--- a/src/main/java/net/starlark/java/eval/StarlarkInt.java
+++ b/src/main/java/net/starlark/java/eval/StarlarkInt.java
@@ -81,10 +81,85 @@
/**
* Returns the int denoted by a literal string in the specified base, as if by the Starlark
- * expression {@code int(str, base)}.
+ * expression {@code int(s, base)}.
+ *
+ * @throws NumberFormatException if the input is invalid.
*/
- public static StarlarkInt parse(String str, int base) throws NumberFormatException {
- return MethodLibrary.parseInt(str, base);
+ public static StarlarkInt parse(String s, int base) {
+ String stringForErrors = s;
+
+ if (s.isEmpty()) {
+ throw new NumberFormatException("empty string");
+ }
+
+ // +/- prefix?
+ boolean isNegative = false;
+ char c = s.charAt(0);
+ if (c == '+') {
+ s = s.substring(1);
+ } else if (c == '-') {
+ s = s.substring(1);
+ isNegative = true;
+ }
+
+ String digits = s;
+
+ // 0b 0o 0x prefix?
+ if (s.length() > 1 && s.charAt(0) == '0') {
+ int prefixBase = 0;
+ c = s.charAt(1);
+ if (c == 'b' || c == 'B') {
+ prefixBase = 2;
+ } else if (c == 'o' || c == 'O') {
+ prefixBase = 8;
+ } else if (c == 'x' || c == 'X') {
+ prefixBase = 16;
+ }
+ if (prefixBase != 0) {
+ digits = s.substring(2); // strip prefix
+ if (base == 0) {
+ base = prefixBase;
+ } else if (base != prefixBase) {
+ throw new NumberFormatException(
+ String.format(
+ "invalid base-%d literal: %s (%s prefix wants base %d)",
+ base, Starlark.repr(stringForErrors), s.substring(0, 2), prefixBase));
+ }
+ }
+ }
+
+ // No prefix, no base? Use decimal.
+ if (digits == s && base == 0) {
+ // Don't infer base when input starts with '0' due to octal/decimal ambiguity.
+ if (s.length() > 1 && s.charAt(0) == '0') {
+ throw new NumberFormatException(
+ "cannot infer base when string begins with a 0: " + Starlark.repr(stringForErrors));
+ }
+ base = 10;
+ }
+ if (base < 2 || base > 36) {
+ throw new NumberFormatException(
+ String.format("invalid base %d (want 2 <= base <= 36)", base));
+ }
+
+ // Do not allow Long.parseLong and new BigInteger to accept another +/- sign.
+ if (digits.startsWith("+") || digits.startsWith("-")) {
+ throw new NumberFormatException(
+ String.format("invalid base-%d literal: %s", base, Starlark.repr(stringForErrors)));
+ }
+
+ StarlarkInt result;
+ try {
+ result = StarlarkInt.of(Long.parseLong(digits, base));
+ } catch (NumberFormatException unused1) {
+ try {
+ result = StarlarkInt.of(new BigInteger(digits, base));
+ } catch (NumberFormatException unused2) {
+ throw new NumberFormatException(
+ String.format("invalid base-%d literal: %s", base, Starlark.repr(stringForErrors)));
+ }
+ }
+ return isNegative ? StarlarkInt.uminus(result) : result;
}
// Subclass for values exactly representable in a Java int.
@@ -216,13 +291,17 @@
/** Returns this StarlarkInt as a string of decimal digits. */
@Override
public String toString() {
- // TODO(adonovan): opt: avoid Number allocation
- return toNumber().toString();
+ if (this instanceof Int32) {
+ return Integer.toString(((Int32) this).v);
+ } else if (this instanceof Int64) {
+ return Long.toString(((Int64) this).v);
+ } else {
+ return toBigInteger().toString();
+ }
}
@Override
public void repr(Printer printer) {
- // TODO(adonovan): opt: avoid Number and String allocations.
printer.append(toString());
}
diff --git a/src/test/java/net/starlark/java/eval/testdata/int_constructor.star b/src/test/java/net/starlark/java/eval/testdata/int_constructor.star
index 973cc15..9d4cc54 100644
--- a/src/test/java/net/starlark/java/eval/testdata/int_constructor.star
+++ b/src/test/java/net/starlark/java/eval/testdata/int_constructor.star
@@ -64,6 +64,7 @@
assert_eq(int('016', 8), 14)
assert_eq(int('016', 16), 22)
assert_eq(int('0', 0), 0)
+assert_eq(int('0x0b10', 16), 0x0b10)
int('0xFF', 8) ### invalid base-8 literal: "0xFF"
---
int('016', 0) ### cannot infer base when string begins with a 0: "016"
@@ -103,3 +104,7 @@
int('1.5') ### invalid base-10 literal: "1.5"
---
int('ab') ### invalid base-10 literal: "ab"
+---
+int('--1') ### invalid base-10 literal: "--1"
+---
+int('-0x-10', 16) ### invalid base-16 literal: "-0x-10"
