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Merged
UdeshyaDhungana merged 4 commits into from
Apr 24, 2026
Merged

Parameter Expansion Updates #290

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991d4f4
Update tests according to the stage instructions; cover edge cases
UdeshyaDhungana Apr 24, 2026
dc51612
Add ZSH fallback pattern in declare_assignment_test_case.go
UdeshyaDhungana Apr 24, 2026
b1716ee
Correct grammar in comment
UdeshyaDhungana Apr 24, 2026
b565635
Update panic message in declare_print_missing_variable_test_case.go
UdeshyaDhungana Apr 24, 2026
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2 changes: 1 addition & 1 deletion internal/stage_pex2.go
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Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ func testPEX2(stageHarness *test_case_harness.TestCaseHarness) error {

missingVariable := "missing_variable_" + strconv.Itoa(random.RandomInt(1, 100))

testCase := test_cases.DeclarePrintErrorTestCase{
testCase := test_cases.DeclarePrintMissingVariableTestCase{
Variable: missingVariable,
}

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4 changes: 2 additions & 2 deletions internal/stage_pex3.go
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Expand Up @@ -33,8 +33,8 @@ func testPEX3(stageHarness *test_case_harness.TestCaseHarness) error {
}

missingVariable := "missing_" + random.RandomWords(1)[0]
printErrorTestCase := test_cases.DeclarePrintErrorTestCase{Variable: missingVariable}
if err := printErrorTestCase.Run(asserter, shell, logger); err != nil {
printMissingVariableTestCase := test_cases.DeclarePrintMissingVariableTestCase{Variable: missingVariable}
if err := printMissingVariableTestCase.Run(asserter, shell, logger); err != nil {
return err
}

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20 changes: 13 additions & 7 deletions internal/stage_pex4.go
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Expand Up @@ -19,27 +19,33 @@ func testPEX4(stageHarness *test_case_harness.TestCaseHarness) error {
return err
}

words := random.RandomWords(4)
words := random.RandomWords(6)

// Valid assignment: underscore-prefixed name
// Valid assignment: name starting with an underscore
validVariable := "_" + words[0]
validVariableValue := words[1]
if err := (test_cases.DeclareAssignmentTestCase{Variable: validVariable, Value: validVariableValue}).Run(asserter, shell, logger); err != nil {
underscorePrefixedAssignment := test_cases.DeclareAssignmentTestCase{Variable: validVariable, Value: validVariableValue}
if err := underscorePrefixedAssignment.Run(asserter, shell, logger); err != nil {
return err
}

// Invalid assignment: name starting with a digit
invalidVariable := fmt.Sprintf("%d%s", random.RandomInt(2, 9), words[2])
invalidDigitPrefixedVariable := fmt.Sprintf("%d%s", random.RandomInt(2, 9), words[2])
invalidVariableValue := words[3]
if err := (test_cases.DeclareAssignmentTestCase{Variable: invalidVariable, Value: invalidVariableValue}).Run(asserter, shell, logger); err != nil {
digitPrefixedAssignment := test_cases.DeclareAssignmentTestCase{Variable: invalidDigitPrefixedVariable, Value: invalidVariableValue}
if err := digitPrefixedAssignment.Run(asserter, shell, logger); err != nil {
return err
}

if err := (test_cases.DeclarePrintTestCase{Variable: validVariable, Value: validVariableValue}).Run(asserter, shell, logger); err != nil {
// Invalid assignment: name with a hyphen in the middle
hyphenInMiddleVariable := words[4] + "-" + words[5]
hyphenInMiddleAssignment := test_cases.DeclareAssignmentTestCase{Variable: hyphenInMiddleVariable, Value: validVariableValue}
if err := hyphenInMiddleAssignment.Run(asserter, shell, logger); err != nil {
return err
}

if err := (test_cases.DeclarePrintErrorTestCase{Variable: invalidVariable}).Run(asserter, shell, logger); err != nil {
printValidVariable := test_cases.DeclarePrintTestCase{Variable: validVariable, Value: validVariableValue}
if err := printValidVariable.Run(asserter, shell, logger); err != nil {
return err
}

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30 changes: 18 additions & 12 deletions internal/stage_pex5.go
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Expand Up @@ -34,8 +34,8 @@ func testPEX5(stageHarness *test_case_harness.TestCaseHarness) error {
}

// Declare two variables with valid names and random values
words := random.RandomWords(4)
integerSuffixes := random.RandomInts(1, 10, 2)
words := random.RandomWords(5)
integerSuffixes := random.RandomInts(0, 10, 2)
variableName1 := fmt.Sprintf(
"%s_%d",
strings.ToUpper(words[0][:1])+words[0][1:],
Expand All @@ -46,32 +46,38 @@ func testPEX5(stageHarness *test_case_harness.TestCaseHarness) error {
strings.ToUpper(words[1][:1])+words[1][1:],
integerSuffixes[1],
)
varValue1 := words[2]
varValue2 := words[3]
variableValue1 := words[2]
variableValue2 := words[3]
literalPrefix := words[4]

if err := (test_cases.DeclareAssignmentTestCase{Variable: variableName1, Value: varValue1}).Run(asserter, shell, logger); err != nil {
assignVariable1 := test_cases.DeclareAssignmentTestCase{Variable: variableName1, Value: variableValue1}
if err := assignVariable1.Run(asserter, shell, logger); err != nil {
return err
}
if err := (test_cases.DeclareAssignmentTestCase{Variable: variableName2, Value: varValue2}).Run(asserter, shell, logger); err != nil {

assignVariable2 := test_cases.DeclareAssignmentTestCase{Variable: variableName2, Value: variableValue2}
if err := assignVariable2.Run(asserter, shell, logger); err != nil {
return err
}

// Run the executable with $VAR1 $VAR2 — shell must expand before passing args
command := fmt.Sprintf("%s $%s $%s", executableName, variableName1, variableName2)
// Run the executable with:
// $VAR1 — standalone expansion
// literalPrefix_$VAR2 — expansion embedded mid-word (no braces)
command := fmt.Sprintf("%s $%s %s_$%s", executableName, variableName1, literalPrefix, variableName2)
expectedLines := []string{
"Program was passed 3 args (including program name).",
fmt.Sprintf("Arg #0 (program name): %s", executableName),
fmt.Sprintf("Arg #1: %s", varValue1),
fmt.Sprintf("Arg #2: %s", varValue2),
fmt.Sprintf("Arg #1: %s", variableValue1),
fmt.Sprintf("Arg #2: %s_%s", literalPrefix, variableValue2),
fmt.Sprintf("Program Signature: %s", commandMetadata),
}

testCase := test_cases.CommandWithMultilineResponseTestCase{
bareExpansionCall := test_cases.CommandWithMultilineResponseTestCase{
Command: command,
MultiLineAssertion: assertions.NewMultiLineAssertion(expectedLines),
SuccessMessage: "✓ Received expected response",
}
if err := testCase.Run(asserter, shell, logger); err != nil {
if err := bareExpansionCall.Run(asserter, shell, logger); err != nil {
return err
}

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23 changes: 13 additions & 10 deletions internal/stage_pex6.go
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Original file line number Diff line number Diff line change
Expand Up @@ -33,8 +33,7 @@ func testPEX6(stageHarness *test_case_harness.TestCaseHarness) error {
return err
}

// Declare two variables with valid names and random values
words := random.RandomWords(6)
words := random.RandomWords(7)
integerSuffixes := random.RandomInts(1, 10, 2)
variableName1 := fmt.Sprintf(
"%s_%d",
Expand All @@ -50,22 +49,26 @@ func testPEX6(stageHarness *test_case_harness.TestCaseHarness) error {
variableValue2 := words[3]
literalPrefix := words[4]
literalSuffix := words[5]
literalSuffix2 := words[6]

if err := (test_cases.DeclareAssignmentTestCase{Variable: variableName1, Value: variableValue1}).Run(asserter, shell, logger); err != nil {
assignVar1 := test_cases.DeclareAssignmentTestCase{Variable: variableName1, Value: variableValue1}
if err := assignVar1.Run(asserter, shell, logger); err != nil {
return err
}
if err := (test_cases.DeclareAssignmentTestCase{Variable: variableName2, Value: variableValue2}).Run(asserter, shell, logger); err != nil {
assignVar2 := test_cases.DeclareAssignmentTestCase{Variable: variableName2, Value: variableValue2}
if err := assignVar2.Run(asserter, shell, logger); err != nil {
return err
}

// Run the executable with ${VAR1} embedded between random literal prefix/suffix,
// and ${VAR2} as a standalone brace-expansion argument.
// Run the executable with:
// prefix_${VAR1}_suffix — braces in the middle of a word
// ${VAR2}_literal — braces at the start of a word
argument1 := fmt.Sprintf("%s_${%s}_%s", literalPrefix, variableName1, literalSuffix)
argument2 := fmt.Sprintf("${%s}", variableName2)
argument2 := fmt.Sprintf("${%s}_%s", variableName2, literalSuffix2)
command := fmt.Sprintf("%s %s %s", executableName, argument1, argument2)

expectedArgument1 := fmt.Sprintf("%s_%s_%s", literalPrefix, variableValue1, literalSuffix)
expectedArgument2 := variableValue2
expectedArgument2 := fmt.Sprintf("%s_%s", variableValue2, literalSuffix2)

expectedLines := []string{
"Program was passed 3 args (including program name).",
Expand All @@ -75,12 +78,12 @@ func testPEX6(stageHarness *test_case_harness.TestCaseHarness) error {
fmt.Sprintf("Program Signature: %s", commandMetadata),
}

testCase := test_cases.CommandWithMultilineResponseTestCase{
bracedExpansionCall := test_cases.CommandWithMultilineResponseTestCase{
Command: command,
MultiLineAssertion: assertions.NewMultiLineAssertion(expectedLines),
SuccessMessage: "✓ Received expected response",
}
if err := testCase.Run(asserter, shell, logger); err != nil {
if err := bracedExpansionCall.Run(asserter, shell, logger); err != nil {
return err
}

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22 changes: 15 additions & 7 deletions internal/stage_pex7.go
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Original file line number Diff line number Diff line change
Expand Up @@ -32,33 +32,41 @@ func testPEX7(stageHarness *test_case_harness.TestCaseHarness) error {
return err
}

existingValue := random.RandomWords(1)[0]
if err := (test_cases.DeclareAssignmentTestCase{Variable: "existing", Value: existingValue}).Run(asserter, shell, logger); err != nil {
words := random.RandomWords(2)
variableName := words[0]
variableValue := words[1]

assignVariable := test_cases.DeclareAssignmentTestCase{Variable: variableName, Value: variableValue}
if err := assignVariable.Run(asserter, shell, logger); err != nil {
return err
}

integerSuffixes := random.RandomInts(1, 99, 2)
integerSuffixes := random.RandomInts(0, 10, 3)

command := fmt.Sprintf(
"%s ${missing_var_%d}_suffix ${existing} ${missing_var_%d}",
"%s ${missing_var_%d}_suffix ${%s} ${missing_var_%d} $missing_var_%d",
executableName,
integerSuffixes[0],
variableName,
integerSuffixes[1],
integerSuffixes[2],
)

expectedLines := []string{
"Program was passed 3 args (including program name).",
fmt.Sprintf("Arg #0 (program name): %s", executableName),
"Arg #1: _suffix",
fmt.Sprintf("Arg #2: %s", existingValue),
fmt.Sprintf("Arg #2: %s", variableValue),
fmt.Sprintf("Program Signature: %s", commandMetadata),
}

testCase := test_cases.CommandWithMultilineResponseTestCase{
missingVarExpansionCall := test_cases.CommandWithMultilineResponseTestCase{
Command: command,
MultiLineAssertion: assertions.NewMultiLineAssertion(expectedLines),
SuccessMessage: "✓ Received expected response",
}
if err := testCase.Run(asserter, shell, logger); err != nil {

if err := missingVarExpansionCall.Run(asserter, shell, logger); err != nil {
return err
}

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6 changes: 5 additions & 1 deletion internal/test_cases/declare_assignment_test_case.go
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Original file line number Diff line number Diff line change
Expand Up @@ -33,14 +33,18 @@ func (t DeclareAssignmentTestCase) Run(asserter *logged_shell_asserter.LoggedShe
}

expectedOutput := fmt.Sprintf("declare: `%s': not a valid identifier", assignment)

testCase := CommandResponseTestCase{
Command: fmt.Sprintf("declare %s", assignment),
ExpectedOutput: expectedOutput,
FallbackPatterns: []*regexp.Regexp{
// bash prefixes with "bash: "
regexp.MustCompile(fmt.Sprintf("^bash: declare: `%s': not a valid identifier$", regexp.QuoteMeta(assignment))),
// zsh uses "not an identifier" phrasing
// zsh uses "not an identifier" for names starting with a digit
regexp.MustCompile(fmt.Sprintf(`^declare: not an identifier: %s$`, regexp.QuoteMeta(t.Variable))),
// zsh uses "not valid in this context"
// for names with valid starting character but with invalid characters in the middle
regexp.MustCompile(fmt.Sprintf(`^declare: not valid in this context: %s$`, regexp.QuoteMeta(t.Variable))),
},
SuccessMessage: "✓ Received expected response",
}
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9 changes: 4 additions & 5 deletions ...st_cases/declare_print_error_test_case.go → ...clare_print_missing_variable_test_case.go
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Expand Up @@ -9,21 +9,20 @@ import (
"github.com/codecrafters-io/tester-utils/logger"
)

// DeclarePrintErrorTestCase tests `declare -p VAR` when the variable does not exist.
// DeclarePrintMissingVariableTestCase tests `declare -p VAR` when the variable does not exist.
// Expected output: declare: VAR: not found
type DeclarePrintErrorTestCase struct {
type DeclarePrintMissingVariableTestCase struct {
Variable string
}

func (t DeclarePrintErrorTestCase) Run(asserter *logged_shell_asserter.LoggedShellAsserter, shell *shell_executable.ShellExecutable, logger *logger.Logger) error {
func (t DeclarePrintMissingVariableTestCase) Run(asserter *logged_shell_asserter.LoggedShellAsserter, shell *shell_executable.ShellExecutable, logger *logger.Logger) error {
fallbackPatterns := []*regexp.Regexp{
regexp.MustCompile(fmt.Sprintf(`^bash: declare: %s: not found$`, regexp.QuoteMeta(t.Variable))),
regexp.MustCompile(fmt.Sprintf(`^declare: no such variable: %s$`, regexp.QuoteMeta(t.Variable))),
}

if !isValidIdentifier(t.Variable) {
// zsh rejects invalid identifiers passed to -p
fallbackPatterns = append(fallbackPatterns, regexp.MustCompile(fmt.Sprintf(`^declare: bad argument to -p: %s$`, regexp.QuoteMeta(t.Variable))))
panic(fmt.Sprintf("Codecrafters Internal Error - DeclarePrintMissingVariableTestCase called on invalid identifier %s", t.Variable))
}

testCase := CommandResponseTestCase{
Expand Down
24 changes: 12 additions & 12 deletions internal/test_helpers/fixtures/bash/parameter_expansion/pass
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Expand Up @@ -41,12 +41,12 @@ Debug = true
[your-program] $ declare 5raspberry=apple
[your-program] bash: declare: `5raspberry=apple': not a valid identifier
[tester::#DB8] ✓ Received expected response
[your-program] $ declare pear-grape=orange
[your-program] bash: declare: `pear-grape=orange': not a valid identifier
[tester::#DB8] ✓ Received expected response
[your-program] $ declare -p _pineapple
[your-program] declare -- _pineapple="orange"
[tester::#DB8] ✓ Received expected response
[your-program] $ declare -p 5raspberry
[your-program] bash: declare: 5raspberry: not found
[tester::#DB8] ✓ Received expected response
[your-program] $ 
[tester::#DB8] Test passed.

Expand All @@ -55,15 +55,15 @@ Debug = true
[tester::#GE9] [setup] Available executables:
[tester::#GE9] [setup] - custom_exe_6864
[tester::#GE9] Running ./your_shell.sh
[your-program] $ declare Grape_1=strawberry
[your-program] $ declare Grape_2=strawberry
[tester::#GE9] ✓ Received expected response
[your-program] $ declare Pear_2=banana
[your-program] $ declare Pear_3=banana
[tester::#GE9] ✓ Received expected response
[your-program] $ custom_exe_6864 $Grape_1 $Pear_2
[your-program] $ custom_exe_6864 $Grape_2 raspberry_$Pear_3
[your-program] Program was passed 3 args (including program name).
[your-program] Arg #0 (program name): custom_exe_6864
[your-program] Arg #1: strawberry
[your-program] Arg #2: banana
[your-program] Arg #2: raspberry_banana
[your-program] Program Signature: 2314588360
[tester::#GE9] ✓ Received expected response
[your-program] $ 
Expand All @@ -78,11 +78,11 @@ Debug = true
[tester::#BR2] ✓ Received expected response
[your-program] $ declare Pineapple_9=pear
[tester::#BR2] ✓ Received expected response
[your-program] $ custom_exe_5355 grape_${Raspberry_2}_banana ${Pineapple_9}
[your-program] $ custom_exe_5355 grape_${Raspberry_2}_banana ${Pineapple_9}_orange
[your-program] Program was passed 3 args (including program name).
[your-program] Arg #0 (program name): custom_exe_5355
[your-program] Arg #1: grape_mango_banana
[your-program] Arg #2: pear
[your-program] Arg #2: pear_orange
[your-program] Program Signature: 4420233970
[tester::#BR2] ✓ Received expected response
[your-program] $ 
Expand All @@ -93,13 +93,13 @@ Debug = true
[tester::#MY0] [setup] Available executables:
[tester::#MY0] [setup] - custom_exe_8866
[tester::#MY0] Running ./your_shell.sh
[your-program] $ declare existing=mango
[your-program] $ declare mango=orange
[tester::#MY0] ✓ Received expected response
[your-program] $ custom_exe_8866 ${missing_var_8}_suffix ${existing} ${missing_var_46}
[your-program] $ custom_exe_8866 ${missing_var_9}_suffix ${mango} ${missing_var_7} $missing_var_6
[your-program] Program was passed 3 args (including program name).
[your-program] Arg #0 (program name): custom_exe_8866
[your-program] Arg #1: _suffix
[your-program] Arg #2: mango
[your-program] Arg #2: orange
[your-program] Program Signature: 7313273050
[tester::#MY0] ✓ Received expected response
[your-program] $ 
Expand Down
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