1 /*
<lambda>null2 * Copyright (c) Meta Platforms, Inc. and affiliates.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package com.facebook.ktfmt.testutil
18
19 import com.facebook.ktfmt.debughelpers.PrintAstVisitor
20 import com.facebook.ktfmt.format.Formatter
21 import com.facebook.ktfmt.format.FormattingOptions
22 import com.facebook.ktfmt.format.Parser
23 import com.google.common.truth.FailureMetadata
24 import com.google.common.truth.Subject
25 import com.google.common.truth.Truth
26 import org.junit.Assert
27
28 /**
29 * Verifies the given code passes through formatting, and stays the same at the end
30 *
31 * @param code a code string that continas an optional first line made of "---" in the case
32 * [deduceMaxWidth] is true. For example:
33 * ```
34 * --------------------
35 * // exactly 20 `-` above
36 * fun f()
37 * ```
38 *
39 * @param deduceMaxWidth if this is true the code string should start with a line of "-----" in the
40 * beginning to indicate the max width to format by
41 */
42 fun assertFormatted(
43 code: String,
44 formattingOptions: FormattingOptions = FormattingOptions(),
45 deduceMaxWidth: Boolean = false
46 ) {
47 val first = code.lines().first()
48 var deducedCode = code
49 var maxWidth = FormattingOptions.DEFAULT_MAX_WIDTH
50 val isFirstLineAMaxWidthMarker = first.all { it == '-' }
51 if (deduceMaxWidth) {
52 if (!isFirstLineAMaxWidthMarker) {
53 throw RuntimeException(
54 "deduceMaxWidth is false, please remove the first dashes only line from the code (i.e. ---)")
55 }
56 deducedCode = code.substring(code.indexOf('\n') + 1)
57 maxWidth = first.length
58 } else {
59 if (isFirstLineAMaxWidthMarker) {
60 throw RuntimeException(
61 "When deduceMaxWidth is true the first line need to be all dashes only (i.e. ---)")
62 }
63 }
64 assertThatFormatting(deducedCode)
65 .withOptions(formattingOptions.copy(maxWidth = maxWidth))
66 .isEqualTo(deducedCode)
67 }
68
assertThatFormattingnull69 fun assertThatFormatting(code: String): FormattedCodeSubject {
70 fun codes(): Subject.Factory<FormattedCodeSubject, String> {
71 return Subject.Factory { metadata, subject -> FormattedCodeSubject(metadata, subject) }
72 }
73 return Truth.assertAbout(codes()).that(code)
74 }
75
76 class FormattedCodeSubject(metadata: FailureMetadata, private val code: String) :
77 Subject(metadata, code) {
78 private var options: FormattingOptions = FormattingOptions()
79 private var allowTrailingWhitespace = false
80
withOptionsnull81 fun withOptions(options: FormattingOptions): FormattedCodeSubject {
82 this.options = options
83 return this
84 }
85
allowTrailingWhitespacenull86 fun allowTrailingWhitespace(): FormattedCodeSubject {
87 this.allowTrailingWhitespace = true
88 return this
89 }
90
isEqualTonull91 fun isEqualTo(expectedFormatting: String) {
92 if (!allowTrailingWhitespace && expectedFormatting.lines().any { it.endsWith(" ") }) {
93 throw RuntimeException(
94 "Expected code contains trailing whitespace, which the formatter usually doesn't output:\n" +
95 expectedFormatting
96 .lines()
97 .map { if (it.endsWith(" ")) "[$it]" else it }
98 .joinToString("\n"))
99 }
100 val actualFormatting: String
101 try {
102 actualFormatting = Formatter.format(options, code)
103 if (actualFormatting != expectedFormatting) {
104 reportError(code)
105 println("# Output: ")
106 println("#".repeat(20))
107 println(actualFormatting)
108 println("# Expected: ")
109 println("#".repeat(20))
110 println(expectedFormatting)
111 println("#".repeat(20))
112 println(
113 "Need more information about the break operations?" +
114 "Run test with assertion with \"FormattingOptions(debuggingPrintOpsAfterFormatting = true)\"")
115 }
116 } catch (e: Error) {
117 reportError(code)
118 throw e
119 }
120 Assert.assertEquals(expectedFormatting, actualFormatting)
121 }
122
reportErrornull123 private fun reportError(code: String) {
124 val file = Parser.parse(code)
125 println("# Parse tree of input: ")
126 println("#".repeat(20))
127 file.accept(PrintAstVisitor())
128 println()
129 println("# Input: ")
130 println("#".repeat(20))
131 println(code)
132 println()
133 }
134 }
135