Asterisk imports parsing; Pussyfooting around stdlib

std/assembly/string.ts

@@ -1,98 +1,197 @@
+const EMPTY: String = changetype<string,String>("");
+
 @global()
 export class String {
+  // [key: number]: string;
 
   private ptr: usize;
-  readonly length: u32;
 
-  constructor(ptr: usize, len: u32) {
+  readonly length: i32;
+
+  constructor(ptr: usize, lenght: i32) {
     this.ptr = ptr;
-    this.length = len;
+    this.length = lenght;
   }
 
-  charAt(index: u32): String {
-    assert(this != null && index < this.length);
-    return new String(this.ptr + (index << 1), 1);
+  charAt(pos: i32): String {
+    assert(this != null);
+    return pos < 0 || pos >= this.length ? EMPTY
+         : new String(this.ptr + (<usize>pos << 1), 1);
   }
 
-  charCodeAt(index: u32): u16 {
-    assert(this != null && index < this.length);
-    return load<u16>(this.ptr + (index << 1));
+  charCodeAt(pos: i32): i32 {
+    assert(this != null);
+    return pos < 0 || pos >= this.length ? -1 // NaN
+         : load<u16>(this.ptr + (<usize>pos << 1));
+  }
+
+  codePointAt(pos: i32): i32 {
+    assert(this != null);
+    if (pos < 0 || pos >= this.length)
+      return -1; // undefined
+    let first: i32 = <i32>load<u16>(this.ptr + (<usize>pos << 1));
+    if (first < 0xD800 || first > 0xDBFF || pos + 1 == this.length)
+      return first;
+    let second: i32 = <i32>load<u16>(this.ptr + ((<usize>pos + 1) << 1));
+    if (second < 0xDC00 || second > 0xDFFF)
+      return first;
+    return ((first - 0xD800) << 10) + (second - 0xDC00) + 0x10000;
   }
 
   @operator("+")
   concat(other: String): String {
-    assert(this != null && other != null);
-    const len: u32 = this.length + other.length;
-    const ptr: usize = Heap.allocate(len << 1);
-    Heap.copy(ptr, this.ptr, this.length << 1);
-    Heap.copy(ptr, this.ptr + (len << 1), other.length << 1);
-    return new String(ptr, len);
+    assert(this != null);
+    assert(other != null);
+    const thisLen: isize = this.length;
+    const otherLen: isize = other.length;
+    const len: usize = thisLen + otherLen;
+    return new String(
+      Heap.copy(
+        Heap.copy(
+          Heap.allocate(len << 1),
+          this.ptr,
+          thisLen << 1
+        ) + (thisLen << 1),
+        other.ptr,
+        otherLen << 1
+      ),
+      <i32>len
+    );
   }
 
-  endsWith(other: String): bool {
-    assert(this != null && other != null);
-    if (other.length > this.length)
+  endsWith(searchString: String, endPosition: i32 = 0x7fffffff): bool {
+    assert(this != null);
+    assert(searchString != null);
+    let end: isize = <isize>min<i32>(max<i32>(endPosition, 0), this.length);
+    let searchLength: isize = searchString.length;
+    let start: isize = end - searchLength;
+    if (start < 0)
       return false;
-    for (let i: u32 = this.length - other.length, j: u32 = 0, k: u32 = this.length; i < k;)
-      if (this.charCodeAt(i++) != other.charCodeAt(j++))
-        return false;
-    return true;
+    return !Heap.compare(this.ptr + (start << 1), searchString.ptr, searchLength << 1);
   }
 
   @operator("==")
   equals(other: String): bool {
-    assert(this != null && other != null);
-    if (this.length != other.length)
+    assert(this != null);
+    assert(other != null);
+    return this.length != other.length ? false
+         : !Heap.compare(this.ptr, other.ptr, <usize>this.length);
+  }
+
+  includes(searchString: String, position: i32 = 0): bool {
+    return this.indexOf(searchString, position) != -1;
+  }
+
+  indexOf(searchString: String, position: i32 = 0): i32 {
+    assert(this != null);
+    assert(searchString != null);
+    let pos: isize = position;
+    let len: isize = this.length;
+    let start: isize = min<isize>(max<isize>(pos, 0), len);
+    let searchLen: isize = searchString.length;
+    for (let k: usize = start; <isize>k + searchLen <= len; ++k)
+      if (!Heap.compare(this.ptr + (k << 1), searchString.ptr, searchLen << 1))
+        return <i32>k;
+    return -1;
+  }
+
+  startsWith(searchString: String, position: i32 = 0): bool {
+    assert(this != null);
+    assert(searchString != null);
+    let pos: isize = position;
+    let len: isize = this.length;
+    let start: isize = min<isize>(max<isize>(position, 0), len);
+    let searchLength: isize = searchString.length;
+    if (searchLength + start > len)
       return false;
-    for (let i: u32 = 0, k: u32 = this.length; i < k; ++i)
-      if (this.charCodeAt(i) != other.charCodeAt(i))
-        return false;
-    return true;
+    return !Heap.compare(this.ptr + (start << 1), searchString.ptr, searchLength << 1);
   }
 
-  indexOf(other: String): u32 {
-    assert(this != null && other != null);
-    throw new Error("not implemented");
-  }
-
-  startsWith(other: String): bool {
-    assert(this != null && other != null);
-    if (other.length > this.length)
-      return false;
-    for (let i: u32 = 0, k: u32 = other.length; i < k; ++i)
-      if (this.charCodeAt(i) != other.charCodeAt(i))
-        return false;
-    return true;
-  }
-
-  substr(start: u32, length: u32 = <u32>-1): String {
+  substr(start: i32, length: i32 = i32.MAX_VALUE): String {
     assert(this != null);
-    if (start >= this.length)
-      return changetype<string,String>("");
-    const len: u32 = min<u32>(length, this.length - start);
-    return new String(this.ptr + (start << 1), len);
+    let intStart: isize = start;
+    let end: isize = length;
+    let size: isize = this.length;
+    if (intStart < 0)
+      intStart = max<isize>(size + intStart, 0);
+    let resultLength: isize = min<isize>(max<isize>(end, 0), size - intStart);
+    if (resultLength < 0)
+      return EMPTY;
+    return new String(this.ptr + (intStart << 1), <i32>resultLength);
   }
 
-  substring(start: u32, end: u32 = <u32>-1): String {
+  substring(start: i32, end: i32 = i32.MAX_VALUE): String {
     assert(this != null);
-    if (start >= this.length || end <= start)
-      return changetype<string,String>("");
-    const len: u32 = min<u32>(end - start, this.length - start);
-    return new String(this.ptr + (start << 1), len);
+    let len: i32 = this.length;
+    let finalStart: i32 = min<i32>(max<i32>(start, 0), len);
+    let finalEnd: i32 = min<i32>(max<i32>(end, 0), len);
+    let from: i32 = min<i32>(finalStart, finalEnd);
+    let to: i32 = max<i32>(finalStart, finalEnd);
+    len = to - from;
+    if (!len)
+      return EMPTY;
+    if (!from && to == this.length)
+      return this;
+    return new String(this.ptr + (from << 1), len);
   }
 
-  trim(): string {
+  trim(): String {
     assert(this != null);
-    throw new Error("not implemented");
+    let length: usize = this.length;
+    while (length && isWhiteSpaceOrLineTerminator(load<u16>(this.ptr + (length << 1))))
+      --length;
+    let start: usize = 0;
+    while (start < length && isWhiteSpaceOrLineTerminator(load<u16>(this.ptr + (start << 1)))) {
+      ++start; --length;
+    }
+    if (!length)
+      return EMPTY;
+    if (!start && length == this.length)
+      return this;
+    return new String(this.ptr + (start << 1), length);
   }
 
-  trimLeft(): string {
+  trimLeft(): String {
     assert(this != null);
-    throw new Error("not implemented");
+    let start: isize = 0;
+    let len: isize = this.length;
+    while (start < len && isWhiteSpaceOrLineTerminator(load<u16>(this.ptr + (start << 1))))
+      ++start;
+    if (!start)
+      return this;
+    return new String(this.ptr + (start << 1), <i32>(len - start));
   }
 
-  trimRight(): string {
+  trimRight(): String {
     assert(this != null);
-    throw new Error("not implemented");
+    let len: isize = this.length;
+    while (len > 0 && isWhiteSpaceOrLineTerminator(load<u16>(this.ptr + (len << 1))))
+      --len;
+    if (len <= 0)
+      return EMPTY;
+    if (<i32>len == this.length)
+      return this;
+    return new String(this.ptr, <i32>len);
+  }
+}
+
+function isWhiteSpaceOrLineTerminator(c: u16): bool {
+  switch (c) {
+
+    case 10:    // <LF>
+    case 13:    // <CR>
+    case 8232:  // <LS>
+    case 8233:  // <PS>
+
+    case 9:     // <TAB>
+    case 11:    // <VT>
+    case 12:    // <FF>
+    case 32:    // <SP>
+    case 160:   // <NBSP>
+    case 65279: // <ZWNBSP>
+
+      return true;
+    default:
+      return false;
   }
 }