100% code-coverage by removing deadcode
kaizhu256 opened this issue · comments
in commit a422783,
the following snippets appear to be deadcode. they will be replaced with internal-assertions just in case they're actually reachable. if anyone can figure out some weird javascript-code that can reach the branches below, please let me know, so i can add extra coverage tests!
diff --git a/jslint.js b/jslint.js
index 141f38f..65c6d7e 100755
--- a/jslint.js
+++ b/jslint.js
@@ -2062,9 +2062,10 @@ function are_similar(a, b) {
// cause: "0&&0"
- if (a === b) {
- return true;
- }
+ assert_or_throw(a !== b, "Expected a !== b.");
+// if (a === b) {
+// return true;
+// }
if (Array.isArray(a)) {
return (
Array.isArray(b)
@@ -2077,9 +2078,10 @@ function are_similar(a, b) {
})
);
}
- if (Array.isArray(b)) {
- return false;
- }
+ assert_or_throw(!Array.isArray(b), "Expected !Array.isArray(b).");
+// if (Array.isArray(b)) {
+// return false;
+// }
if (a.id === "(number)" && b.id === "(number)") {
return a.value === b.value;
}
@@ -2102,16 +2104,25 @@ function are_similar(a, b) {
return false;
}
if (a.arity === b.arity && a.id === b.id) {
+
+// cause: "aa.bb&&aa.bb"
+
if (a.id === ".") {
return (
are_similar(a.expression, b.expression)
&& are_similar(a.name, b.name)
);
}
+
+// cause: "+0&&+0"
+
if (a.arity === "unary") {
return are_similar(a.expression, b.expression);
}
if (a.arity === "binary") {
+
+// cause: "aa[0]&&aa[0]"
+
return (
a.id !== "("
&& are_similar(a.expression[0], b.expression[0])
@@ -2128,9 +2139,13 @@ function are_similar(a, b) {
&& are_similar(a.expression[2], b.expression[2])
);
}
- if (a.arity === "function" && a.arity === "regexp") {
- return false;
- }
+ assert_or_throw(
+ a.arity !== "function" && a.arity !== "regexp",
+ "Expected a.arity !== \"function\" && a.arity !== \"regexp\"."
+ );
+// if (a.arity === "function" && a.arity === "regexp") {
+// return false;
+// }
// cause: "undefined&&undefined"here is diff-comparison of the 12 places where "deadcode" was replaced with assertion-checks in jslint to get full-code-coverage @
https://github.com/jslint-org/jslint/compare/v2020.11.6..v2021.5.30#diff-4822639e8179a5188bdfd8cfb48d9e103a7dcc1f2b1036465ab7017d4166c2a8
the purpose of this issue is to track regression/blame in case any of the deadcode raises assertion-check (and turns out not be dead afterall).
diff --git a/jslint.js b/jslint.js
old mode 100644
new mode 100755
index 4f365ef..3fc58fa
--- a/jslint.js
+++ b/jslint.js
@@ -561,7 +557,28 @@ function warn_at(code, line, column, a, b, c, d) {
if (d !== undefined) {
warning.d = d;
}
- warning.message = supplant(bundle[code] || code, warning);
+ warning.message = bundle[code].replace(rx_supplant, function (
+ ignore,
+ filling
+ ) {
+ assert_or_throw(
+ warning[filling] !== undefined,
+ "Expected warning[filling] !== undefined."
+ );
+// Probably deadcode.
+// return (
+// replacement !== undefined
+// ? replacement
+// : found
+// );
+ return warning[filling];
+ });
@@ -880,21 +926,27 @@ function tokenize(source) {
typeof allowed === "boolean"
|| typeof allowed === "object"
) {
- if (
- value === ""
- || value === "true"
- || value === undefined
- ) {
+ if (value === "true" || value === undefined) {
option[name] = true;
if (Array.isArray(allowed)) {
populate(allowed, declared_globals, false);
}
- } else if (value === "false") {
- option[name] = false;
} else {
- warn("bad_option_a", the_comment, name + ":" + value);
+ assert_or_throw(
+ value === "false",
+ `Expected value === "false".`
+ );
+ option[name] = false;
+// Probably deadcode.
+// } else if (value === "false") {
+// option[name] = false;
+// } else {
+// warn("bad_option_a", the_comment, name + ":" + value);
}
} else {
@@ -1045,54 +1124,68 @@ function tokenize(source) {
}
function choice() {
+ let follow;
- function group() {
+// Parse sequence of characters in regexp.
+
+ while (true) {
+ switch (char) {
+ case "":
+ case "/":
+ case "]":
+ case ")":
+ if (!follow) {
+
+// cause: "/ /"
+
+ warn_at("expected_regexp_factor_a", line, column, char);
+ }
+
+// Match a choice (a sequence that can be followed by | and another choice).
+
+ assert_or_throw(
+ !(char === "|"),
+ `Expected !(char === "|").`
+ );
+// Probably deadcode.
+// if (char === "|") {
+// next_char("|");
+// return choice();
+// }
+ return;
+ case "(":
@@ -1937,21 +2155,31 @@ function is_weird(thing) {
}
function are_similar(a, b) {
- if (a === b) {
- return true;
- }
+
+// cause: "0&&0"
+
+ assert_or_throw(!(a === b), `Expected !(a === b).`);
+// Probably deadcode.
+// if (a === b) {
+// return true;
+// }
if (Array.isArray(a)) {
return (
Array.isArray(b)
&& a.length === b.length
&& a.every(function (value, index) {
+
+// cause: "`${0}`&&`${0}`"
+
return are_similar(value, b[index]);
})
);
}
- if (Array.isArray(b)) {
- return false;
- }
+ assert_or_throw(!Array.isArray(b), `Expected !Array.isArray(b).`);
+// Probably deadcode.
+// if (Array.isArray(b)) {
+// return false;
+// }
if (a.id === "(number)" && b.id === "(number)") {
return a.value === b.value;
}
@@ -1991,17 +2228,31 @@ function are_similar(a, b) {
);
}
if (a.arity === "ternary") {
+
+// cause: "aa=(``?``:``)&&(``?``:``)"
+
return (
are_similar(a.expression[0], b.expression[0])
&& are_similar(a.expression[1], b.expression[1])
&& are_similar(a.expression[2], b.expression[2])
);
}
- if (a.arity === "function" && a.arity === "regexp") {
- return false;
- }
+ assert_or_throw(
+ !(a.arity === "function" || a.arity === "regexp"),
+ `Expected !(a.arity === "function" || a.arity === "regexp").`
+ );
+// Probably deadcode.
+// if (a.arity === "function" || a.arity === "regexp") {
+// return false;
+// }
@@ -2913,14 +3327,19 @@ function do_function(the_function) {
name = the_function.name;
}
the_function.level = functionage.level + 1;
- if (mega_mode) {
- warn("unexpected_a", the_function);
- }
+ assert_or_throw(!mega_mode, `Expected !mega_mode.`);
+// Probably deadcode.
+// if (mega_mode) {
+// warn("unexpected_a", the_function);
+// }
// Don't make functions in loops. It is inefficient, and it can lead to scoping
// errors.
if (functionage.loop > 0) {
@@ -4024,21 +4817,25 @@ function pop_block() {
blockage = block_stack.pop();
}
-function activate(name) {
- name.dead = false;
- if (name.expression !== undefined) {
- walk_expression(name.expression);
- if (name.id === "{" || name.id === "[") {
- name.names.forEach(subactivate);
- } else {
+function action_var(thing) {
+ thing.names.forEach(function (name) {
+ name.dead = false;
+ if (name.expression !== undefined) {
+ walk_expression(name.expression);
+ assert_or_throw(
+ !(name.id === "{" || name.id === "["),
+ `Expected !(name.id === "{" || name.id === "[").`
+ );
+// Probably deadcode.
+// if (name.id === "{" || name.id === "[") {
+// name.names.forEach(subactivate);
+// } else {
+// name.init = true;
+// }
name.init = true;
}
@@ -4182,11 +5004,20 @@ postaction("assignment", function (thing) {
const lvalue = thing.expression[0];
if (thing.id === "=") {
if (thing.names !== undefined) {
- if (Array.isArray(thing.names)) {
- thing.names.forEach(init_variable);
- } else {
- init_variable(thing.names);
- }
+
+// cause: "if(0){aa=0}"
+
+ assert_or_throw(
+ !Array.isArray(thing.names),
+ `Expected !Array.isArray(thing.names).`
+ );
+// Probably deadcode.
+// if (Array.isArray(thing.names)) {
+// thing.names.forEach(init_variable);
+// } else {
+// init_variable(thing.names);
+// }
+ init_variable(thing.names);
} else {
if (lvalue.id === "[" || lvalue.id === "{") {
lvalue.expression.forEach(function (thing) {
@@ -4533,19 +5463,37 @@ function delve(the_function) {
if (id !== "ignore") {
const name = the_function.context[id];
if (name.parent === the_function) {
+
+// cause: "let aa=function bb(){return;};"
+
if (
name.used === 0
- && (
- name.role !== "function"
- || name.parent.arity !== "unary"
+ && assert_or_throw(
+ name.role !== "function",
+ `Expected name.role !== "function".`
)
+// Probably deadcode.
+// && (
+// name.role !== "function"
+// || name.parent.arity !== "unary"
+// )
) {
@@ -4593,12 +5561,23 @@ function whitage() {
}
function expected_at(at) {
+ assert_or_throw(
+ !(right === undefined),
+ `Expected !(right === undefined).`
+ );
+// Probably deadcode.
+// if (right === undefined) {
+// right = next_token;
+// }
warn(
"expected_a_at_b_c",
right,
artifact(right),
fudge + at,
@@ -4638,19 +5653,42 @@ function whitage() {
);
}
} else {
- if (open) {
- const at = (
- free
- ? margin
- : margin + 8
- );
- if (right.from < at) {
- expected_at(at);
- }
- } else {
- if (right.from !== margin + 8) {
- expected_at(margin + 8);
- }
+
+// from:
+// } else if (
+// right.arity === "binary"
+// && right.id === "("
+// && free
+// ) {
+// no_space();
+// } else if (
+
+ assert_or_throw(open, `Expected open.`);
+ assert_or_throw(free, `Expected free.`);
+// Probably deadcode.
+// if (open) {
+// const at = (
+// free
+// ? margin
+// : margin + 8
+// );
+// if (right.from < at) {
+// expected_at(at);
+// }
+// } else {
+// if (right.from !== margin + 8) {
+// expected_at(margin + 8);
+// }
+// }