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Checks.d
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Checks.d
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// Copyright (c) 2014- Facebook
// License: Boost License 1.0, http://boost.org/LICENSE_1_0.txt
// @author Andrei Alexandrescu ([email protected])
import std.algorithm, std.array, std.ascii, std.conv, std.exception, std.path,
std.range, std.stdio, std.string;
import Tokenizer, FileCategories;
bool c_mode;
enum explicitThrowSpec = "/* may throw */";
/*
* Errors vs. Warnings vs. Advice:
*
* Lint errors will be raised regardless of whether the line was
* edited in the change. Warnings will be ignored by Arcanist
* unless the change actually modifies the line the warning occurs
* on. Advice is even weaker than a warning.
*
* Please select errors vs. warnings intelligently. Too much spam
* on lines you don't touch reduces the value of lint output.
*
*/
void lintError(CppLexer.Token tok, const string error) {
stderr.writef("%.*s:%u: %s",
cast(uint) tok.file_.length, tok.file_,
cast(uint) tok.line_,
error);
}
immutable string warningPrefix = "Warning: ";
void lintWarning(CppLexer.Token tok, const string warning) {
// The FbcodeCppLinter just looks for the text "Warning" in the
// message.
lintError(tok, warningPrefix ~ warning);
}
void lintAdvice(CppLexer.Token tok, string advice) {
// The FbcodeCppLinter just looks for the text "Advice" in the
// message.
lintError(tok, "Advice: " ~ advice);
}
bool atSequence(Range)(Range r, const CppLexer.TokenType2[] list...) {
foreach (t; list) {
if (r.empty || t != r.front.type_) {
return false;
}
r.popFront;
}
return true;
}
string getSucceedingWhitespace(Token[] v) {
if (v.length < 2) return "";
return v[1].precedingWhitespace_;
}
bool isInMacro(Token[] v, const long idx) {
// Walk backwards through the tokens, continuing until a newline
// that is not preceded by a backslash is encountered (i.e. a
// true line break).
for (long i = idx; i >= 0; --i) {
if (v[i..$].atSequence(tk!"#", tk!"identifier") &&
v[i + 1].value == "define") return true;
if (i == 0) return false;
string pws = v[i].precedingWhitespace_;
auto pos = lastIndexOf(pws, '\n');
if (pos == -1) continue;
if (pos != 0) return false;
if (v[i - 1].type_ != tk!"\\") return false;
}
return false;
}
struct IncludedPath {
string path;
bool angleBrackets;
bool nolint;
bool precompiled;
}
bool getIncludedPath(R)(ref R r, out IncludedPath ipath) {
if (!r.atSequence(tk!"#", tk!"identifier") || r[1].value != "include") {
return false;
}
r.popFrontN(2);
bool found = false;
if (r.front.value_ == "PRECOMPILED") {
ipath.precompiled = true;
found = true;
}
if (r.front.type_ == tk!"string_literal") {
string val = r.front.value;
ipath.path = val[1 .. val.length - 1];
found = true;
} else if (r.front.type_ == tk!"<") {
r.popFront;
ipath.path = "";
for (; !r.empty; r.popFront) {
if (r.front.type_ == tk!">") {
break;
}
ipath.path ~= r.front.value;
}
ipath.angleBrackets = true;
found = true;
}
if (!found) {
return false;
}
ipath.nolint = getSucceedingWhitespace(r).canFind("nolint");
return true;
}
/*
* Skips a template parameter list or argument list, somewhat
* heuristically. Basically, scans forward tracking nesting of <>
* brackets and parenthesis to find the end of the list. This function
* takes as input an iterator as well as an optional parameter containsArray
* that is set to true if the outermost nest contains an array
*
* Known unsupported case: TK_RSHIFT can end a template instantiation
* in C++0x as if it were two TK_GREATERs.
* (E.g. vector<vector<int>>.)
*
* Returns: iterator pointing to the final TK_GREATER (or TK_EOF if it
* didn't finish).
*/
R skipTemplateSpec(R)(R r, bool* containsArray = null) {
assert(r.front.type_ == tk!"<");
uint angleNest = 1;
uint parenNest = 0;
if (containsArray) {
*containsArray = false;
}
r.popFront;
for (; r.front.type_ != tk!"\0"; r.popFront) {
if (r.front.type_ == tk!"(") {
++parenNest;
continue;
}
if (r.front.type_ == tk!")") {
--parenNest;
continue;
}
// Ignore angles inside of parens. This avoids confusion due to
// integral template parameters that use < and > as comparison
// operators.
if (parenNest > 0) {
continue;
}
if (r.front.type_ == tk!"[") {
if (angleNest == 1 && containsArray) {
*containsArray = true;
}
continue;
}
if (r.front.type_ == tk!"<") {
++angleNest;
continue;
}
if (r.front.type_ == tk!">") {
if (!--angleNest) {
break;
}
continue;
}
if (r.front.type_ == tk!">>") {
// it is possible to munch a template from within a template, so we
// only want to consume one of the '>>'
angleNest -= 2;
if (angleNest <= 0) break;
continue;
}
}
return r;
}
/*
* Returns whether `it' points to a token that is a reserved word for
* a built in type.
*/
bool atBuiltinType(R)(R it) {
return it.front.type_.among(tk!"double", tk!"float", tk!"int", tk!"short",
tk!"unsigned", tk!"long", tk!"signed", tk!"void", tk!"bool", tk!"wchar_t",
tk!"char") != 0;
}
/*
* heuristically read a potentially namespace-qualified identifier,
* advancing `it' in the process.
*
* Returns: a vector of all the identifier values involved, or an
* empty vector if no identifier was detected.
*/
string[] readQualifiedIdentifier(R)(ref R it) {
string[] result;
for (; it.front.type_.among(tk!"identifier", tk!"::"); it.popFront) {
if (it.front.type_ == tk!"identifier") {
result ~= it.front.value_;
}
}
return result;
}
/*
* starting from a left curly brace, skips until it finds the matching
* (balanced) right curly brace. Does not care about whether other characters
* within are balanced.
*
* Returns: iterator pointing to the final TK_RCURL (or TK_EOF if it
* didn't finish).
*/
R skipBlock(R)(R r) {
enforce(r.front.type_ == tk!"{");
uint openBraces = 1;
r.popFront;
for (; r.front.type_ != tk!"\0"; r.popFront) {
if (r.front.type_ == tk!"{") {
++openBraces;
continue;
}
if (r.front.type_ == tk!"}") {
if (!--openBraces) {
break;
}
continue;
}
}
return r;
}
/*
* Iterates through to find all class declarations and calls the callback
* with an iterator pointing to the first token in the class declaration.
* The iterator is guaranteed to have type TK_CLASS, TK_STRUCT, or TK_UNION.
*
* Note: The callback function is responsible for the scope of its search, as
* the vector of tokens passed may (likely will) extend past the end of the
* class block.
*
* Returns the sum of the results from calling the callback on
* each declaration.
*/
uint iterateClasses(alias callback)(Token[] v) {
uint result = 0;
for (auto it = v; !it.empty; it.popFront) {
if (it.atSequence(tk!"template", tk!"<")) {
it.popFront;
it = skipTemplateSpec(it);
continue;
}
if (it.front.type_.among(tk!"class", tk!"struct", tk!"union")) {
result += callback(it, v);
}
}
return result;
}
/*
* Starting from a function name or one of its arguments, skips the entire
* function prototype or function declaration (including function body).
*
* Implementation is simple: stop at the first semicolon, unless an opening
* curly brace is found, in which case we stop at the matching closing brace.
*
* Returns: iterator pointing to the final TK_RCURL or TK_SEMICOLON, or TK_EOF
* if it didn't finish.
*/
R skipFunctionDeclaration(R)(R r) {
r.popFront;
for (; r.front.type_ != tk!"\0"; r.popFront) {
if (r.front.type_ == tk!";") { // prototype
break;
} else if (r.front.type_ == tk!"{") { // full declaration
r = skipBlock(r);
break;
}
}
return r;
}
/**
* Represent an argument or the name of a function.
* first is an iterator that points to the start of the argument.
* last is an iterator that points to the token right after the end of the
* argument.
*/
struct Argument {
Token[] tox;
ref Token first() { return tox.front; }
ref Token last() { return tox.back; }
}
struct FunctionSpec {
Argument functionName;
Argument[] args;
bool isNoexcept;
bool explicitThrows;
bool isConst;
bool isDeleted;
bool isDefault;
};
string formatArg(Argument arg) {
string result;
foreach (i, a; arg.tox) {
if (i != 0 && !a.precedingWhitespace_.empty) {
result ~= ' ';
}
result ~= a.value;
}
return result;
}
string formatFunction(FunctionSpec spec) {
auto result = formatArg(spec.functionName) ~ "(";
foreach (i; 0 .. spec.args.length) {
if (i > 0) {
result ~= ", ";
}
result ~= formatArg(spec.args[i]);
}
result ~= ")";
return result;
}
/**
* Get the list of arguments of a function, assuming that the current
* iterator is at the open parenthesis of the function call. After the
* this method is called, the iterator will be moved to after the end
* of the function call.
* @param i: the current iterator, must be at the open parenthesis of the
* function call.
* @param args: the arguments of the function would be push to the back of args
* @return true if (we believe) that there was no problem during the run and
* false if we believe that something was wrong (most probably with skipping
* template specs.)
*/
bool getRealArguments(ref Token[] r, ref Argument[] args) {
assert(r.front.type_ == tk!"(", text(r));
// the first argument starts after the open parenthesis
auto argStart = r[1 .. $];
int parenCount = 1;
do {
if (r.front.type_ == tk!"\0") {
// if we meet EOF before the closing parenthesis, something must be wrong
// with the template spec skipping
return false;
}
r.popFront;
switch (r.front.type_.id) {
case tk!"(".id: parenCount++;
break;
case tk!")".id: parenCount--;
break;
case tk!"<".id: // This is a heuristic which would fail when < is used with
// the traditional meaning in an argument, e.g.
// memset(&foo, a < b ? c : d, sizeof(foo));
// but currently we have no way to distinguish that use of
// '<' and
// memset(&foo, something<A,B>(a), sizeof(foo));
// We include this heuristic in the hope that the second
// use of '<' is more common than the first.
r = skipTemplateSpec(r);
break;
case tk!",".id: if (parenCount == 1) {
// end an argument of the function we are looking at
args ~=
Argument(argStart[0 .. argStart.length - r.length]);
argStart = r[1 .. $];
}// otherwise we are in an inner function, so do nothing
break;
default: break;
}
} while (parenCount != 0);
if (argStart !is r) {
args ~= Argument(argStart[0 .. argStart.length - r.length]);
}
return true;
}
/**
* Get the argument list of a function, with the first argument being the
* function name plus the template spec.
* @param i: the current iterator, must be at the function name. At the end of
* the method, i will be pointing at the close parenthesis of the function call
* @param functionName: the function name will be stored here
* @param args: the arguments of the function would be push to the back of args
* @return true if (we believe) that there was no problem during the run and
* false if we believe that something was wrong (most probably with skipping
* template specs.)
*/
bool getFunctionSpec(ref Token[] r, ref FunctionSpec spec) {
auto r1 = r;
r.popFront;
if (r.front.type_ == tk!"<") {
r = skipTemplateSpec(r);
if (r.front.type_ == tk!"\0") {
return false;
}
r.popFront;
}
assert(r1.length >= r.length);
spec.functionName.tox = r1[0 .. r1.length - r.length];
if (!getRealArguments(r, spec.args)) {
return false;
}
auto r2 = r;
assert(r2.front.type_ == tk!")");
r2.popFront;
while (true) {
if (r2.front.precedingWhitespace_.canFind(explicitThrowSpec)) {
spec.explicitThrows = true;
}
if (r2.front.type_ == tk!"noexcept") {
spec.isNoexcept = true;
r2.popFront;
continue;
}
if (r2.front.type_ == tk!"const") {
spec.isConst = true;
r2.popFront;
continue;
}
if (r2.front.type_ == tk!"=") {
r2.popFront;
if (r2.front.type_ == tk!"delete") {
spec.isDeleted = true;
r2.popFront;
continue;
}
if (r2.front.type_ == tk!"default") {
spec.isDefault = true;
r2.popFront;
continue;
}
}
break;
}
return true;
}
uint checkInitializeFromItself(string fpath, Token[] tokens) {
auto firstInitializer = [
tk!":", tk!"identifier", tk!"(", tk!"identifier", tk!")"
];
auto nthInitialier = [
tk!",", tk!"identifier", tk!"(", tk!"identifier", tk!")"
];
uint result = 0;
for (auto it = tokens; !it.empty; it.popFront) {
if (it.atSequence(firstInitializer) || it.atSequence(nthInitialier)) {
it.popFront;
auto outerIdentifier = it.front;
it.popFrontN(2);
auto innerIdentifier = it.front;
bool isMember = outerIdentifier.value_.back == '_'
|| outerIdentifier.value_.startsWith("m_");
if (isMember && outerIdentifier.value_ == innerIdentifier.value_) {
lintError(outerIdentifier, text(
"Looks like you're initializing class member [",
outerIdentifier.value_, "] with itself.\n")
);
++result;
}
}
}
return result;
}
/**
* Lint check: check for blacklisted sequences of tokens.
*/
uint checkBlacklistedSequences(string fpath, CppLexer.Token[] v) {
struct BlacklistEntry {
CppLexer.TokenType2[] tokens;
string descr;
bool cpponly;
}
const static BlacklistEntry[] blacklist = [
BlacklistEntry([tk!"volatile"],
"'volatile' does not make your code thread-safe. If multiple threads are " ~
"sharing data, use std::atomic or locks. In addition, 'volatile' may " ~
"force the compiler to generate worse code than it could otherwise. " ~
"For more about why 'volatile' doesn't do what you think it does, see " ~
"http://www.kernel.org/doc/Documentation/" ~
"volatile-considered-harmful.txt.\n",
true), // C++ only.
];
const static CppLexer.TokenType2[][] exceptions = [
[CppLexer.tk!"asm", CppLexer.tk!"volatile"],
];
uint result = 0;
bool isException = false;
foreach (i; 0 .. v.length) {
foreach (e; exceptions) {
if (atSequence(v[i .. $], e)) { isException = true; break; }
}
foreach (ref entry; blacklist) {
if (!atSequence(v[i .. $], entry.tokens)) { continue; }
if (isException) { isException = false; continue; }
if (c_mode && entry.cpponly == true) { continue; }
if (v[i].precedingWhitespace_.canFind("nolint")) { continue; }
lintWarning(v[i], entry.descr);
++result;
}
}
return result;
}
uint checkBlacklistedIdentifiers(string fpath, CppLexer.Token[] v) {
uint result = 0;
string[string] banned = [
"strtok" :
"strtok() is not thread safe, and has safer alternatives. Consider " ~
"folly::split or strtok_r as appropriate.\n",
"strncpy" :
"strncpy is very often used in error; see " ~
"http://meyering.net/crusade-to-eliminate-strncpy/\n"
];
foreach (ref t; v) {
if (t.type_ != tk!"identifier") continue;
auto mapIt = t.value_ in banned;
if (!mapIt) continue;
lintError(t, *mapIt);
++result;
}
return result;
}
/**
* Lint check: no #defined names use an identifier reserved to the
* implementation.
*
* These are enforcing rules that actually apply to all identifiers,
* but we're only raising warnings for #define'd ones right now.
*/
uint checkDefinedNames(string fpath, Token[] v) {
// Define a set of exception to rules
static bool[string] okNames;
if (okNames.length == 0) {
static string[] okNamesInit = [
"__STDC_LIMIT_MACROS",
"__STDC_FORMAT_MACROS",
"_GNU_SOURCE",
"_XOPEN_SOURCE",
];
foreach (i; 0 .. okNamesInit.length) {
okNames[okNamesInit[i]] = true;
}
}
uint result = 0;
foreach (i, ref t; v) {
if (i == 0 || v[i - 1].type_ != tk!"#" || t.type_ != tk!"identifier"
|| t.value != "define") continue;
if (v[i - 1].precedingWhitespace_.canFind("nolint")) continue;
const t1 = v[i + 1];
auto const sym = t1.value_;
if (t1.type_ != tk!"identifier") {
// This actually happens because people #define private public
// for unittest reasons
lintWarning(t1, text("you're not supposed to #define ", sym, "\n"));
continue;
}
if (sym.length >= 2 && sym[0] == '_' && isUpper(sym[1])) {
if (sym in okNames) {
continue;
}
lintWarning(t, text("Symbol ", sym, " invalid." ~
" A symbol may not start with an underscore followed by a " ~
"capital letter.\n"));
++result;
} else if (sym.length >= 2 && sym[0] == '_' && sym[1] == '_') {
if (sym in okNames) {
continue;
}
lintWarning(t, text("Symbol ", sym, " invalid." ~
" A symbol may not begin with two adjacent underscores.\n"));
++result;
} else if (!c_mode /* C is less restrictive about this */ &&
sym.canFind("__")) {
if (sym in okNames) {
continue;
}
lintWarning(t, text("Symbol ", sym, " invalid." ~
" A symbol may not contain two adjacent underscores.\n"));
++result;
}
}
return result;
}
/**
* Lint check: only the following forms of catch are allowed:
*
* catch (Type &)
* catch (const Type &)
* catch (Type const &)
* catch (Type & e)
* catch (const Type & e)
* catch (Type const & e)
*
* Type cannot be built-in; this function enforces that it's
* user-defined.
*/
uint checkCatchByReference(string fpath, Token[] v) {
uint result = 0;
foreach (i, ref e; v) {
if (e.type_ != tk!"catch") continue;
if (getSucceedingWhitespace(v[i..$]).canFind("nolint")) continue;
size_t focal = 1;
enforce(v[i + focal].type_ == tk!"(", // a "(" comes always after catch
text(v[i + focal].file_, ":", v[i + focal].line_,
": Invalid C++ source code, please compile before lint."));
++focal;
if (v[i + focal].type_ == tk!"...") {
// catch (...
continue;
}
if (v[i + focal].type_ == tk!"const") {
// catch (const
++focal;
}
if (v[i + focal].type_ == tk!"typename") {
// catch ([const] typename
++focal;
}
if (v[i + focal].type_ == tk!"::") {
// catch ([const] [typename] ::
++focal;
}
// At this position we must have an identifier - the type caught,
// e.g. FBException, or the first identifier in an elaborate type
// specifier, such as facebook::FancyException<int, string>.
if (v[i + focal].type_ != tk!"identifier") {
const t = v[i + focal];
lintWarning(t, "Symbol " ~ t.value_ ~ " invalid in " ~
"catch clause. You may only catch user-defined types.\n");
++result;
continue;
}
++focal;
// We move the focus to the closing paren to detect the "&". We're
// balancing parens because there are weird corner cases like
// catch (Ex<(1 + 1)> & e).
for (size_t parens = 0; ; ++focal) {
enforce(focal < v.length,
text(v[i + focal].file_, ":", v[i + focal].line_,
": Invalid C++ source code, please compile before lint."));
if (v[i + focal].type_ == tk!")") {
if (parens == 0) break;
--parens;
} else if (v[i + focal].type_ == tk!"(") {
++parens;
}
}
// At this point we're straight on the closing ")". Backing off
// from there we should find either "& identifier" or "&" meaning
// anonymous identifier.
if (v[i + focal - 1].type_ == tk!"&") {
// check! catch (whatever &)
continue;
}
if (v[i + focal - 1].type_ == tk!"identifier" &&
v[i + focal - 2].type_ == tk!"&") {
// check! catch (whatever & ident)
continue;
}
// Oopsies times
const t = v[i + focal - 1];
// Get the type string
string theType;
foreach (j; 2 .. focal - 1) {
if (j > 2) theType ~= " ";
theType ~= v[i + j].value;
}
lintError(t, text("Symbol ", t.value_, " of type ", theType,
" caught by value. Use catch by (preferably const) reference " ~
"throughout.\n"));
++result;
}
return result;
}
/**
* Lint check: any usage of throw specifications is a lint error.
*
* We track whether we are at either namespace or class scope by
* looking for class/namespace tokens and tracking nesting level. Any
* time we go into a { } block that's not a class or namespace, we
* disable the lint checks (this is to avoid false positives for throw
* expressions).
*/
uint checkThrowSpecification(string, Token[] v) {
uint result = 0;
// Check for throw specifications inside classes
result += v.iterateClasses!(
function uint(Token[] it, Token[] v) {
uint result = 0;
it = it.find!(a => a.type_ == tk!"{");
if (it.empty) {
return result;
}
it.popFront;
const destructorSequence =
[tk!"~", tk!"identifier", tk!"(", tk!")",
tk!"throw", tk!"(", tk!")"];
for (; !it.empty && it.front.type_ != tk!"\0"; it.popFront) {
// Skip warnings for empty throw specifications on destructors,
// because sometimes it is necessary to put a throw() clause on
// classes deriving from std::exception.
if (it.atSequence(destructorSequence)) {
it.popFrontN(destructorSequence.length - 1);
continue;
}
// This avoids warning if the function is named "what", to allow
// inheriting from std::exception without upsetting lint.
if (it.front.type_ == tk!"identifier" && it.front.value_ == "what") {
it.popFront;
auto sequence = [tk!"(", tk!")", tk!"const",
tk!"throw", tk!"(", tk!")"];
if (it.atSequence(sequence)) {
it.popFrontN(sequence.length - 1);
}
continue;
}
if (it.front.type_ == tk!"{") {
it = skipBlock(it);
continue;
}
if (it.front.type_ == tk!"}") {
break;
}
if (it.front.type_ == tk!"throw" && it[1].type_ == tk!"(") {
lintWarning(it.front, "Throw specifications on functions are " ~
"deprecated.\n");
++result;
}
}
return result;
}
);
// Check for throw specifications in functional style code
for (auto it = v; !it.empty; it.popFront) {
// Don't accidentally identify a using statement as a namespace
if (it.front.type_ == tk!"using") {
if (it[1].type_ == tk!"namespace") {
it.popFront;
}
continue;
}
// Skip namespaces, classes, and blocks
if (it.front.type_.among(tk!"namespace", tk!"class", tk!"struct",
tk!"union", tk!"{")) {
auto term = it.find!(x => x.type_ == tk!"{");
if (term.empty) {
break;
}
it = skipBlock(term);
continue;
}
if (it.front.type_ == tk!"throw" && it[1].type_ == tk!"(") {
lintWarning(it.front, "Throw specifications on functions are " ~
"deprecated.\n");
++result;
}
}
return result;
}
/**
* Lint check: balance of #if(#ifdef, #ifndef)/#endif.
*/
uint checkIfEndifBalance(string fpath, Token[] v) {
int openIf = 0;
// Return after the first found error, because otherwise
// even one missed #if can be cause of a lot of errors.
foreach (i, ref e; v) {
if (v[i .. $].atSequence(tk!"#", tk!"if")
|| (v[i .. $].atSequence(tk!"#", tk!"identifier")
&& (v[i + 1].value_ == "ifndef" || v[i + 1].value_ == "ifdef"))) {
++openIf;
} else if (v[i .. $].atSequence(tk!"#", tk!"identifier")
&& v[i + 1].value_ == "endif") {
--openIf;
if (openIf < 0) {
lintError(e, "Unmatched #endif.\n");
return 1;
}
} else if (v[i .. $].atSequence(tk!"#", tk!"else")) {
if (openIf == 0) {
lintError(e, "Unmatched #else.\n");
return 1;
}
}
}
if (openIf != 0) {
lintError(v.back, "Unbalanced #if/#endif.\n");
return 1;
}
return 0;
}
/*
* Lint check: warn about common errors with constructors, such as:
* - single-argument constructors that aren't marked as explicit, to avoid them
* being used for implicit type conversion (C++ only)
* - Non-const copy constructors, or useless const move constructors.
* - Move constructors that aren't marked noexcept
*/
uint checkConstructors(string fpath, Token[] tokensV) {
if (getFileCategory(fpath) == FileCategory.source_c) {
return 0;
}
uint result = 0;
string[] nestedClasses;
const string explicitOverride = "/"~"* implicit *"~"/";
const CppLexer.TokenType2[] stdInitializerSequence =
[tk!"identifier", tk!"::", tk!"identifier", tk!"<"];
const CppLexer.TokenType2[] voidConstructorSequence =
[tk!"identifier", tk!"(", tk!"void", tk!")"];
for (auto tox = tokensV; tox.length; tox.popFront) {
// Avoid mis-identifying a class context due to use of the "class"
// keyword inside a template parameter list.
if (tox.atSequence(tk!"template", tk!"<")) {
tox = skipTemplateSpec(tox[1 .. $]);
continue;
}
// Parse within namespace blocks, but don't do top-level constructor checks.
// To do this, we treat namespaces like unnamed classes so any later
// function name checks will not match against an empty string.
if (tox.front.type_ == tk!"namespace") {
tox.popFront;
for (; tox.front.type_ != tk!"\0"; tox.popFront) {
if (tox.front.type_ == tk!";") {
break;
} else if (tox.front.type_ == tk!"{") {
nestedClasses ~= "";
break;
}
}
continue;
}
// Extract the class name if a class/struct definition is found
if (tox.front.type_ == tk!"class" || tox.front.type_ == tk!"struct") {
tox.popFront;
// If we hit any C-style structs, we'll handle them like we do namespaces:
// continue to parse within the block but don't show any lint errors.
if (tox.front.type_ == tk!"{") {
nestedClasses ~= "";
} else if (tox.front.type_ == tk!"identifier") {
auto classCandidate = tox.front.value_;
for (; tox.front.type_ != tk!"\0"; tox.popFront) {
if (tox.front.type_ == tk!";") {
break;
} else if (tox.front.type_ == tk!"{") {
nestedClasses ~= classCandidate;
break;
}
}
}
continue;
}
// Closing curly braces end the current scope, and should always be balanced
if (tox.front.type_ == tk!"}") {
if (nestedClasses.empty) { // parse fail
return result;
}
nestedClasses.popBack;
continue;
}
// Skip unrecognized blocks. We only want to parse top-level class blocks.
if (tox.front.type_ == tk!"{") {
tox = skipBlock(tox);
continue;
}
// Only check for constructors if we've previously entered a class block
if (nestedClasses.empty) {
continue;
}
// Handle an "explicit" keyword, with or without "constexpr"
bool checkImplicit = true;
if (tox.atSequence(tk!"explicit", tk!"constexpr") ||
tox.atSequence(tk!"constexpr", tk!"explicit")) {
checkImplicit = false;
tox.popFront;
tox.popFront;
}
if (tox.front.type_ == tk!"explicit") {
checkImplicit = false;
tox.popFront;
}
// Skip anything that doesn't look like a constructor
if (!tox.atSequence(tk!"identifier", tk!"(")) {
continue;
} else if (tox.front.value_ != nestedClasses.back) {
tox = skipFunctionDeclaration(tox);
continue;
}
// Suppress error and skip past functions clearly marked as implicit
if (tox.front.precedingWhitespace_.canFind(explicitOverride)) {
checkImplicit = false;
}
// Allow zero-argument void constructors
if (tox.atSequence(voidConstructorSequence)) {
tox = skipFunctionDeclaration(tox);
continue;
}
FunctionSpec spec;
spec.functionName = Argument(tox[0 .. 1]);
if (tox.front.precedingWhitespace_.canFind(explicitThrowSpec)) {
spec.explicitThrows = true;
}
if (!tox.getFunctionSpec(spec)) {
// Parse fail can be due to limitations in skipTemplateSpec, such as with:
// fn(std::vector<boost::shared_ptr<ProjectionOperator>> children);)
return result;
}
// Allow zero-argument constructors
if (spec.args.empty) {
tox = skipFunctionDeclaration(tox);
continue;
}
auto argIt = spec.args[0].tox;
bool foundConversionCtor = false;
bool isConstArgument = false;
if (argIt.front.type_ == tk!"const") {
isConstArgument = true;
argIt.popFront;
}