Simplify SkSL::String by removing unused parts.

- reset, findLastOf: these were entirely unused
- find: already existed in C++11's std::string, can just be inherited
- defaulted constructors: in C++11, these can be inherited directly from
  std::string via 'using'

Change-Id: I1772ef04e49ab905aaada2ec38c1abeb9a8e26bf
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/311039
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>

src/sksl/SkSLString.cpp

@@ -33,16 +33,6 @@ void String::appendf(const char* fmt, ...) {
     va_end(args);
 }
 
-void String::reset() {
-    this->clear();
-}
-
-int String::findLastOf(const char c) const {
-    // Rely on find_last_of and remap the output
-    size_t index = this->find_last_of(c);
-    return (index == std::string::npos ? -1 : index);
-}
-
 void String::vappendf(const char* fmt, va_list args) {
     #define BUFFER_SIZE 256
     char buffer[BUFFER_SIZE];
@@ -59,27 +49,16 @@ void String::vappendf(const char* fmt, va_list args) {
     va_end(reuse);
 }
 
-
-bool String::startsWith(const char* s) const {
-    return !strncmp(c_str(), s, strlen(s));
+bool String::startsWith(const char prefix[]) const {
+    return !strncmp(this->data(), prefix, strlen(prefix));
 }
 
-bool String::endsWith(const char* s) const {
-    size_t len = strlen(s);
-    if (size() < len) {
+bool String::endsWith(const char suffix[]) const {
+    size_t suffixLength = strlen(suffix);
+    if (this->length() < suffixLength) {
         return false;
     }
-    return !strncmp(c_str() + size() - len, s, len);
-}
-
-int String::find(const String& substring, int fromPos) const {
-    return find(substring.c_str(), fromPos);
-}
-
-int String::find(const char* substring, int fromPos) const {
-    SkASSERT(fromPos >= 0);
-    size_t found = INHERITED::find(substring, (size_t) fromPos);
-    return found == std::string::npos ? -1 : found;
+    return !strncmp(this->data() + this->size() - suffixLength, suffix, suffixLength);
 }
 
 String String::operator+(const char* s) const {

src/sksl/SkSLString.h

@@ -57,36 +57,16 @@ bool operator!=(const char* s1, StringFragment s2);
 
 class SK_API String : public std::string {
 public:
-    String() = default;
-    String(const String&) = default;
-    String(String&&) = default;
-    String& operator=(const String&) = default;
-    String& operator=(String&&) = default;
+    using std::string::string;
 
-    String(const char* s)
-    : INHERITED(s) {}
-
-    String(const char* s, size_t size)
-    : INHERITED(s, size) {}
-
-    String(StringFragment s)
-    : INHERITED(s.fChars, s.fLength) {}
+    String(StringFragment s) : INHERITED(s.fChars, s.fLength) {}
 
     static String printf(const char* fmt, ...);
-
     void appendf(const char* fmt, ...);
-    // For API compatibility with SkString's reset (vs. std:string's clear)
-    void reset();
-    // For API compatibility with SkString's findLastOf(vs. find_last_of -> size_t)
-    int findLastOf(const char c) const;
-
     void vappendf(const char* fmt, va_list va);
 
-    bool startsWith(const char* s) const;
-    bool endsWith(const char* s) const;
-
-    int find(const char* substring, int fromPos = 0) const;
-    int find(const String& substring, int fromPos = 0) const;
+    bool startsWith(const char* prefix) const;
+    bool endsWith(const char* suffix) const;
 
     String operator+(const char* s) const;
     String operator+(const String& s) const;
@@ -111,19 +91,13 @@ String operator+(const char* s1, const String& s2);
 bool operator!=(const char* s1, const String& s2);
 
 String to_string(double value);
-
 String to_string(int32_t value);
-
 String to_string(uint32_t value);
-
 String to_string(int64_t value);
-
 String to_string(uint64_t value);
 
 SKSL_INT stoi(const String& s);
-
 SKSL_FLOAT stod(const String& s);
-
 long stol(const String& s);
 
 } // namespace  SkSL

tests/CrbugOssfuzz21688.cpp

@@ -25,6 +25,7 @@ DEF_TEST(crbug_ossfuzz_21688_interfaceblock, reporter) {
     std::unique_ptr<SkSL::Program> program = compiler.convertProgram(SkSL::Program::kFragment_Kind,
                                                                      kProgramText, settings);
     REPORTER_ASSERT(reporter, program == nullptr);
-    REPORTER_ASSERT(reporter, compiler.errorText().find("interface block 'testBlock' must "
-                                                        "contain at least one member") != -1);
+    REPORTER_ASSERT(reporter, compiler.errorText().find(
+                                    "interface block 'testBlock' must "
+                                    "contain at least one member") != SkSL::String::npos);
 }