diff options
Diffstat (limited to 'vendor/github.com/graph-gophers/graphql-go/internal/common/blockstring.go')
-rw-r--r-- | vendor/github.com/graph-gophers/graphql-go/internal/common/blockstring.go | 103 |
1 files changed, 103 insertions, 0 deletions
diff --git a/vendor/github.com/graph-gophers/graphql-go/internal/common/blockstring.go b/vendor/github.com/graph-gophers/graphql-go/internal/common/blockstring.go new file mode 100644 index 00000000..1f7fe813 --- /dev/null +++ b/vendor/github.com/graph-gophers/graphql-go/internal/common/blockstring.go @@ -0,0 +1,103 @@ +// MIT License +// +// Copyright (c) 2019 GraphQL Contributors +// +// Permission is hereby granted, free of charge, to any person obtaining a copy +// of this software and associated documentation files (the "Software"), to deal +// in the Software without restriction, including without limitation the rights +// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +// copies of the Software, and to permit persons to whom the Software is +// furnished to do so, subject to the following conditions: +// +// The above copyright notice and this permission notice shall be included in all +// copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +// SOFTWARE. +// +// This implementation has been adapted from the graphql-js reference implementation +// https://github.com/graphql/graphql-js/blob/5eb7c4ded7ceb83ac742149cbe0dae07a8af9a30/src/language/blockString.js +// which is released under the MIT License above. + +package common + +import ( + "strings" +) + +// Produces the value of a block string from its parsed raw value, similar to +// CoffeeScript's block string, Python's docstring trim or Ruby's strip_heredoc. +// +// This implements the GraphQL spec's BlockStringValue() static algorithm. +func blockString(raw string) string { + lines := strings.Split(raw, "\n") + + // Remove common indentation from all lines except the first (which has none) + ind := blockStringIndentation(lines) + if ind > 0 { + for i := 1; i < len(lines); i++ { + l := lines[i] + if len(l) < ind { + lines[i] = "" + continue + } + lines[i] = l[ind:] + } + } + + // Remove leading and trailing blank lines + trimStart := 0 + for i := 0; i < len(lines) && isBlank(lines[i]); i++ { + trimStart++ + } + lines = lines[trimStart:] + trimEnd := 0 + for i := len(lines) - 1; i > 0 && isBlank(lines[i]); i-- { + trimEnd++ + } + lines = lines[:len(lines)-trimEnd] + + return strings.Join(lines, "\n") +} + +func blockStringIndentation(lines []string) int { + var commonIndent *int + for i := 1; i < len(lines); i++ { + l := lines[i] + indent := leadingWhitespace(l) + if indent == len(l) { + // don't consider blank/empty lines + continue + } + if indent == 0 { + return 0 + } + if commonIndent == nil || indent < *commonIndent { + commonIndent = &indent + } + } + if commonIndent == nil { + return 0 + } + return *commonIndent +} + +func isBlank(s string) bool { + return len(s) == 0 || leadingWhitespace(s) == len(s) +} + +func leadingWhitespace(s string) int { + i := 0 + for _, r := range s { + if r != '\t' && r != ' ' { + break + } + i++ + } + return i +} |